Brenden Holland | Hawaii Pacific University (original) (raw)

RESEARCH SUMMARY OF THE HOLLAND LAB
The Pacific Islands might be considered an environmental microcosm of what is occurring on a global scale. Lessons learned in places like Hawaii, and solutions derived from ecological studies here have direct relevance to the world at large. Hawaii and other islands of the Pacific house sensitive native marine and forest ecosystems that provide critical nutrient, economic, air and water services for human populations. Native terrestrial species such as the achatinelline tree snails require native host trees for their survival, and are sensitive to the presence of established invasive species including plants, insects such as ants, predatory snails, rats, and African chameleons. Therefore forests where tree snails are present can be deemed high priority areas for focused conservation effort, as tree snails are important indicators of ecosystem health. Human populations rely directly on native rain forest for water services, as intact forest ecosystems act as upland reservoirs, capturing and slowly releasing clean water. Hawaii is notorious for its absence of native terrestrial vertebrate lineages (with the exception of birds and a single bat species), there are no native land dwelling mammals, reptiles, or amphibians. However, since the late 19th century, humans have released at least 43 species of frogs, toads lizards, and turtles, 26 of which are currently established, and all of these are predatory. Amazingly, very few studies had been conducted aimed at understanding behaviors and determining the impact of invasive reptiles and amphibians (herpetofauna) on native ecosystems, until Dr. Brenden Holland, PI of the Hawaii Tree Snail Conservation Lab began to investigate the ecology of those species that have ranges which overlap with native forest.
Summaries of a selection of published ecological and conservation biology studies conducted by Dr. Holland and his research group in recent years include:

1.) The first study demonstrating that the devastating predatory snail Euglandina rosea shows a preference for tracking the slime trail of native tree snails versus the intended target agricultural pest species, the giant African snail (Achatina fulica) (Holland et al. 2012).

2.) The first study showing that newly hatched wolf snails are predatory and can feed on prey snails more than three times their own body mass (Sugiura et al. 2011).

3.) The first detection of impacts of Jackson’s chameleons on endemic fauna, including the endangered Oahu tree snail Achatinella mustelina (Holland, Costello & Montgomery 2010)

4.) Detailed impact projections, estimates and long term threat assessment via observed predatory density, gut content analyses and ingestion frequency (Chiaverano & Holland 2014).

5.) Characterization of Chameleon movement behavior and establishment of home range in various forest habitats (Chiaverano, Wright & Holland 2014) using radio-transmitter tracking studies in the field.

6.) Discovered consistent, statistically significant differences in chameleon size and invertebrate prey utilization among different Hawaiian islands, correlated with differences in bite force due to dietary differences in prey hardness and rainfall. This is likely a harbinger of insipient speciation of this species in Hawaii. (Van Kleeck, Chiaverano & Holland in press).

7.) Conducted surveys and collected the predatory invasive wrinkled frog (Glandirana rugosa), dissected and analyzed gut contents for native versus nonnative prey, and compared the results to previous studies of diet in native range (Japan) (Van Kleeck et al. in review).

8.) In a series of studies aimed at understanding the systematics, fisheries management, biogeography and diversification of the Hawaiian opihi, we used a combination of molecular and marine ecology approaches to show that the ancestral source of our native limpet populations is in the region of Japan, and that MPA's would greatly benefit sustainable utilization of this important economic and cultural marine resource (Bird et al 2007; 2011)

9.) We have published papers documenting all of the species of box jellyfish that are present in the Hawaiian Islands (Crow et al. 2014) and linking the number of stinging box jellyfish in each aggregation event for the past 14 years with regional oceanographic conditions (Chiaverano et al. 2013), showing that we can predict influx intensity given certain environmental factors.

Literature Cited

All publications cited are available at the following link:
https://www.researchgate.net/profile/Brenden\_Holland

Contact information: Dr. Brenden Holland
bholland@hawaii.edu 808-956-6176
Pacific Biosciences Research Center
School of Ocean and Earth Science &
Technology
Supervisors: Scott K. Davis and Stephen R. Gittings
Address: Hawaii Pacific University,
College of Natural Sciences
Kaneohe HI 96744

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Publications by Brenden Holland

Zoological Studies, 2023

The hydrozoan family Eirenidae is known scientifically for its morphological plasticity and chall... more The hydrozoan family Eirenidae is known scientifically for its morphological plasticity and challenges in
species identification. We used an integrative taxonomic approach based on morphological, molecular
and life history evidence to systematically assess field-collected medusae of Eirene menoni Kramp
1953 and captive raised polyps of both E. menoni and E. lacteoides Kubota and Horita 1992. Following
morphological review, we updated the genus description to include the presence of rudimentary bulbs
(warts) on the ring canal in at least eight of the 24 valid Eirene species. We propose the potential for the
mature E. menoni hydrotheca to develop into a gonotheca. However, this proposal will require additional
study for verification. We provide validated distribution records from the Indo-Pacific Ocean for E. menoni,
and updated collection records for E. lacteoides from the Yellow and East China Seas, and public
aquaria-cultured specimens from Japan and Hawaii, using cytochrome c oxidase I (COI) sequences that
we generated and compared with those from GenBank. The COI gene reliably separated four species,
each forming a monophyletic clade with strong bootstrap support and low mean intraspecific molecular
divergences (≤ 1%) within clades. However, some of the deeper nodes of the tree remained poorly
resolved, and our analysis failed to demonstrate monophyly among eirenid genera Eirene and Tima. Our
integrative taxonomic approach is essential in confirming species identity within the family Eirenidae and
genus Eirene, and we have also identified a likely range expansion of E. lacteoides to Hawaii.

Zoological Studies, 2023

The hydrozoan family Eirenidae is known scientifically for its morphological plasticity and chall... more The hydrozoan family Eirenidae is known scientifically for its morphological plasticity and challenges in species identification. We used an integrative taxonomic approach based on morphological, molecular and life history evidence to systematically assess field-collected medusae of Eirene menoni Kramp 1953 and captive raised polyps of both E. menoni and E. lacteoides Kubota and Horita 1992. Following morphological review, we updated the genus description to include the presence of rudimentary bulbs (warts) on the ring canal in at least eight of the 24 valid Eirene species. We propose the potential for the mature E. menoni hydrotheca to develop into a gonotheca, however, this will require additional study for verification. We provide validated distribution records from the Indo-Pacific Ocean for E. menoni, and updated collection records for E. lacteoides from the Yellow and East China Seas, and public aquaria-cultured specimens from Japan and Hawaii, using cytochrome c oxidase I (COI) sequences that we generated compared with those from GenBank. The COI gene reliably separated four species, each forming a monophyletic clade with strong bootstrap support and low mean intraspecific molecular divergences (≤ 1%) within clades. However, some of the deeper nodes of the tree remained poorly resolved, and our analysis failed to demonstrate monophyly among eirenid genera Eirene and Tima. Our integrative taxonomic approach is essential in confirming species identity within the family Eirenidae and genus Eirene, and we have also identified a likely range expansion of E. lacteoides to Hawaii.

Science Advances, 2022

Conspicuous social and sexual signals are predicted to experience pronounced character release wh... more Conspicuous social and sexual signals are predicted to experience pronounced character release when natural selection via predation is relaxed. However, we have few good examples of this phenomenon in the wild and none in species with dynamic color change. Here, we show that Jackson's chameleons inadvertently introduced from Kenya to Hawaii (Oahu), where there are no coevolved, native lizard predators, experienced pronounced character release of color signals. Hawaiian chameleons displayed more conspicuous social color signals than Kenyan chameleons during male contests and courtship, were less cryptic in response to bird and snake predators, and showed greater change between display and antipredator color states. Hawaiian chameleon display colors were also more conspicuous in their local than ancestral habitats, consistent with local adaptation of social signals. These results demonstrate that relaxed predation pressure can result in character release of dynamic social signals in introduced species experiencing strong sexual selection.

Journal of Coastal Science, 2021

Jellyfish stings can have substantial negative impacts on ocean recreation and tourism globally. ... more Jellyfish stings can have substantial negative impacts on ocean recreation and tourism globally. In Hawaii, where tourism
comprises a major portion of the state’s economy, the non-lethal stings of the box jellyfish, Alatina alata impact hundreds to
over one thousand Oahu beachgoers annually. Envenomated individuals may experience hypertension, cramping, and nausea
with painful dermatitis. Here we compile and summarize information based on a 25-year influx history, mass stinging events,
sting treatment costs and protocols, and socio-economic impacts on this recurrent phenomenon on the island of Oahu. We
delivered 452 questionnaires to visitors and residents at Waikiki Beach (WB) to access and quantify levels of beach user
awareness and concern regarding box jellyfish presence and stings relative to other coastal hazards. A lack of awareness of
box jellyfish and associated stings at WB was recorded in 56% of visitors and 30% of residents. Box jellyfish warning signage
was observed by only 44% of visitors and 69% of residents. Questionnaire results suggest that additional box jellyfish
communication and education are needed. Such information could be provided at beaches via permanent panels, and at hotels
via kiosks and public service announcements. These efforts to enhance public awareness could reduce both costs and time
spent by Ocean Safety and Lifeguard Services and Emergency Medical Service personnel in treating beachgoer stings.
Increased beachgoer awareness of box jellyfish would improve the WB experience and help mitigate box jellyfish stings.

Zoological Science, 2021

Tima nigroannulata sp. nov. is described from medusae collected in shallow waters of four prefect... more Tima nigroannulata sp. nov. is described from medusae collected in shallow waters of four prefectures on the Pacific coast of Japan (Miyagi, Fukushima, Kanagawa, and Miyazaki), as well as from cultures maintained at two aquaria (Enoshima Aquarium, Kanagawa Prefecture; Tsuruoka City Kamo Aquarium, Yamagata Prefecture). Adult medusae differ from those of other known species of the genus Tima Eschscholtz, 1829 in the following combination of characters: (1) umbrella usually hemispherical or higher, (2) marginal tentacles up to 50 or more in number; and (3) black pigment granules form a ring around the umbrella rim, and sometimes extend onto the tentacles and radial canals. Their hydroids, from aquarium cultures, have stolonal colonies with pedicels of varied length, vestigial hydrothecae, slender and vase-to club-shaped hydranths, and a whorl of about 20 filiform tentacles with an intertentacular web basally. Medusa buds develop singly within gonothecae that arise from the hydrothecal pedicels. The cnidomes of both hydroid and medusa stages comprise heteronemes, provisionally identified as microbasic mastigophores. Medusae of T. nigroannulata are confirmed as a unique, cohesive lineage by comparing mtDNA COI sequence fragments with those from two congeners, resulting in three well-supported reciprocally monophyletic clades, one representing each species. Records of the western Atlantic medusa Tima formosa L. Agassiz, 1862 from Japan overlap those of T. nigroannulata, and are believed to have been based on the new species described herein.

Journal of the Lepidopterists' Society 72(3):218-226. 2018 , 2018

The Mariana eight-spot butterfly (Hypolimnas octocula marianensis) and the Mariana wandering butt... more The Mariana eight-spot butterfly (Hypolimnas octocula marianensis) and the Mariana wandering butterfly (Vagrans egistina) are endemic to the Mariana Islands and both have recently been listed as federally protected under the U.S. Endangered Species Act. We conducted both targeted surveys and grid transect searches on Guam and targeted surveys across the islands of Saipan, Tinian and Rota to locate native hostplants, eggs, caterpillars and adults of these rare insects. Despite having a relatively common hostplant, V. egistina was not found during this study, even in places it had last been found. Although various life stages of H. o. marianensis were documented, the hostplants of this species were heavily impacted by grazing of introduced ungulates; only in native limestone forest with jagged tower karst topography, did hostplants persist, and the butterfly with them. The reasons for the disappearance of V. egistina are not clear, but do not appear to be related to hostplant availability. Our surveys suggest that control of invasive ungulates on Guam will be the single most effective conservation action for Mariana eight-spot recovery , and is essential to any chance of long-term persistence for the species there. H. o. marianensis has significant, unoccupied, hostplant patches on the three northern islands (Rota, Tinian, and Saipan) which might be considered as sites for future translo-cation and reintroduction efforts, in order to reduce the risk of extinction.

Although grazers have long been recognized as top–down architects of plant communities, animal ro... more Although grazers have long been recognized as top–down architects of plant communities, animal roles in determining microbial community composition have seldom been examined, particularly in aboveground systems. To determine the extent to which an animal can shape microbial communities, we conducted a controlled mesocosm study in situ to see if introducing mycophageous tree snails changed phyllosphere fungal community composition relative to matched control mesocosms. Fungal community composition and change was determined by Illumina sequencing of DNA collected from leaf surfaces before snails were introduced, daily for 3 days and weekly for 6 weeks thereafter. Scanning electron microscopy was used to confirm that grazing had occurred, and we recorded 3.5 times more cover of fungal hyphae in control mesocosms compared with those containing snails. Snails do not appear to vector novel microbes and despite grazing, a significant proportion of the initial leaf phyllosphere persisted in the mesocosms. Within-mesocosm diversities of fungi were similar regardless of whether or not snails were added. The greatest differences between the snail-treated and control mesocosms was that grazed mesocosms showed greater infiltration of microbes that were not sampled when the experiment commenced and that the variance in fungal community composition (beta diversity) was greater between leaves in snail-treated mesocosms indicating increased community heterogeneity and ecosystem fragmentation.

Ethology, Ecology & Evolution, 2018

Various aspects of social structure can be important drivers of basic behavioral patterns, includ... more Various aspects of social structure can be important drivers of basic behavioral
patterns, including dispersal, intraspecific niche partitioning, and resource
utilization. Juvenile–adult interactions such as agonistic displays and paedophagic
cannibalism can result in avoidance of adults by juveniles, and can influence
community structure via shifts in ontogenetic habitat use patterns and juvenile
dispersal. In this study, we examined the role of agonistic behavior in determining
differences in habitat utilization between life stages in an ecologically damaging
invasive lizard, Trioceros jacksonii xantholophus, in the Hawaiian Islands. We
tested the hypothesis that intraspecific aggression by adults drives observed
niche separation and juvenile dispersal. In the laboratory, we conducted paired
conspecific trials to assess paedophagic behavior, and staged contests to assess
aggression and response: 57% of adults consumed newborns when paired. In
addition, juveniles fled further, faster, and more often in response to aggressive
adult displays than from other juveniles. To assess the effect of antagonistic
behaviors on juvenile movement and its potential role in and habitat shifts, we
used radio-telemetry and exploited diet comparison to assess resource use in
juveniles versus adults. Though our results suggested no significant difference in
immature versus adult chameleon dispersal, juveniles were found to perch at
significantly lower heights above ground, and exploited different prey types than
did adults. These results suggest that resource partitioning is occurring, but the
immature chameleons are sedentary as are the adults. Due to age-dependent
habitat usage, our results suggest that T. j. xantholophus occupies a broader
niche than previously recognized. These results highlight the importance of studies
focused on patterns of behavior at different developmental stages of invasive
species, which ultimately provide better information allowing prediction of ecological
impacts and range expansion potential.

The importance of pheromones in insect and mammal social systems is well documented , but few stu... more The importance of pheromones in insect and mammal social systems is well documented , but few studies have addressed the role of pheromones in land snail behavior. In this investigation, we used a series of behavioral trials and direct analysis in real time mass spectrometry (MS) to test the hypothesis that land snails use mucous trails in orientation and chemical communication. We worked with six endemic Hawaiian land snail species in four genera, three subfamilies, and two families. We tested conspecific trail following in five of these species, and trail following occurred at a statistically significant frequency for each of the species tested (n=181, p-values ranged <0.0001–0.0494). Percentage of conspecific trials that showed trail following ranged 66.7–94.1%. None of the interspecific tests revealed evidence of trail following among species (n=105, with p-values of 0.0577–0.5000). Juvenile achatinelline snails did not follow trails of conspecific juveniles (n=30, p=0.5722) or adults (n=30, p=0.4278), nor did adults follow juvenile trails (n=30, p=0.5722). Comparative MS analysis of adult and juvenile trails showed distinct chemical signatures in the two groups. Signals corresponding to medium-and long-chain fatty acids and other unidentified small molecules were present in adult but not in juvenile trails. Considered together, these results support the hypotheses that trail following could serve an important social and reproductive function. This discovery provides evidence for the presence of an ephemeral tree snail pheromone, which could have important implications for the conservation of these increasingly rare and threatened species.

Invasive reptiles cause global ecosystem damage and are difficult to control once established. Vi... more Invasive reptiles cause global ecosystem damage and are difficult to control once established. Visual detection and manual capture are time consuming and largely ineffective at eradication, particularly for cryptic species. The Jackson's chameleon (Trioceros jacksonii xantholophus), native to eastern Africa, is popular in the global pet trade and has become established in several localities, including the Hawaiian Islands where it has escaped or been intentionally released into sensitive native forest habitat where it feeds on endangered species. Here we tested an orally delivered, chemical toxicant as a feasible management technique for this invasive lizard in Hawaii. We administered predetermined dosages of powdered acetaminophen to adult chamleoens and determined that the dosage necessary to achieve 95% mortality within 48 h across size classes was 2000 mg/kg, or 90 mg of acetaminophen for an adult average mass of 45 g. Since the liver is known to process acetaminophen in vertebrate taxa, we conducted post mortem histological examination of liver tissue for all specimens at the 48 h time point. Finally, we propose a testable mechanism for field delivery of this oral toxicant following behavioral trials.

Although grazers have long been recognized as top–down architects of plant communities, animal ro... more Although grazers have long been recognized as top–down architects of plant communities, animal roles in determining microbial community composition have seldom been examined, particularly in aboveground systems. To determine the extent to which an animal can shape microbial communities, we conducted a controlled mesocosm study in situ to see if introducing mycophageous tree snails changed phyllosphere fungal community composition relative to matched control mesocosms. Fungal community composition and change was determined by Illumina sequencing of DNA collected from leaf surfaces before snails were introduced, daily for 3 days and weekly for 6 weeks thereafter. Scanning electron microscopy was used to confirm that grazing had occurred, and we recorded 3.5 times more cover of fungal hyphae in control mesocosms compared with those containing snails. Snails do not appear to vector novel microbes and despite grazing, a significant proportion of the initial leaf phyllosphere persisted in the mesocosms. Within-mesocosm diversities of fungi were similar regardless of whether or not snails were added. The greatest differences between the snail-treated and control mesocosms was that grazed mesocosms showed greater infiltration of microbes that were not sampled when the experiment commenced and that the variance in fungal community composition (beta diversity) was greater between leaves in snail-treated mesocosms indicating increased community heterogeneity and ecosystem fragmentation.

Hawaii’s diverse achatinellid tree snails occur almost exclusively in host trees and shrubs that ... more Hawaii’s diverse achatinellid tree snails occur almost exclusively in host trees and shrubs that are native to the Hawaiian Archipelago. A few exceptions to this pattern are known, where an arboreal gastropod population has persisted in introduced plants. On Oahu, Hawaii, the last known population of the single island endemic snail Auriculella diaphana has persisted in nonnative plants for multiple decades, leading to the following question: are there differences in relative fitness of native gastropods in native versus nonnative host plants? To address this we conducted laboratory trials with A. diaphana in three treatment groups, one with the two dominant nonnative host plants from their current distribution, another group with two known primary native host plant species, and a third treatment maintained in cages with a mixture of equal parts nonnative and native plants. Trials were conducted over two 16-week intervals, with 100 snails. Relative fitness was assessed among treatments as survival and reproductive output (number of eggs produced). Results demonstrated that while survival of adult snails was equivalent across treatments (100%), fecundity was significantly higher in cages where native plants were available. Egg production was 20.05-fold and 14.95-fold greater in treatments with 100% and 50% native host plants, respectively, than in treatments with nonnative plants only. These results suggest that native snails persisting in nonnative host plants experience sublethal stress, reflected in a dramatic reduction in reproductive output. Snails in treatments with mixed native and nonnative plants also showed significantly higher reproduction than in nonnative plant cages. We suggest that the observed decreased fecundity is due to diminished nutritional value of the phyllosphere of nonnative vegetation, and that translocation of this and related species occurring in nonnative habitat, to nearby native host plants will be beneficial in terms of relative fitness.

Key Words: Auriculella diaphana, Hawaiian tree snails, biological conservation, native Hawaiian species, ecosystem restoration, relative fitness, resource management, snail reproduction.

Endangered species can be safeguarded against extinction by raising subpopulations in ex situ fac... more Endangered species can be safeguarded against extinction by raising subpopulations in ex situ facilities that mimic their wild habitats. This is difficult when the endangered animal’s diet is cryptic. We present a combined molecular and behavioral approach to assess the ex situ diet of Achatinella a critically endangered genus of tree snail, to determine how diet of captive snails differs from wild snails. Ex situ snails are currently fed biofilms growing on the surface of leaves, as well as a cultured fungus isolated from this same habitat. Amplicon sequencing of DNA extracted from feces of cultured snails confirms that this cultured fungus is abundant in the wild, but that it dominates the diet of the ex situ snail diet (comprising ~38% of sequences). The diet of captive snails is significantly less diverse compared to wild snails. To test the hypothesis that snails have diet preferences, we conducted feeding trials. These used a surrogate snail species, Auriculella diaphana, which is a confamilial Oahu endemic, though non-­‐federally listed. Contrary to our expectations we found that snails do have feeding preferences. Furthermore, our feeding preference trials show that over all other feeding options snails most preferred the “no-­‐microbe” control, which consisted only of potato dextrose agar (PDA). PDA is rich in simple carbohydrates, in contrast to the oligotrophic environment of wild tree-­‐snails. These results suggest further research should focus on calorie budgets of snails and on devising new approaches to supplementing their ex situ diet.

Biological invasions are recognized as a primary driver of large-scale changes in global ecosyste... more Biological invasions are recognized as a primary driver of large-scale changes in global ecosystems. This study
addresses ecomorphological variation in head size within and among populations of an ecologically destructive
invasive predator, and evaluates the potential roles of environmental components in phenotypic differentiation.
We used four size-corrected measurements of head morphology in Jackson’s chameleons, Trioceros jacksonii
xantholophus (N = 319), collected from multiple Hawaiian Islands to assess phenotypic variation among and
within islands. Results of analysis of variance (ANOVA) comparing chameleon head size (PC1) among islands
revealed significant differences (mean difference > 5%) associated with variation in both rainfall and diet
composition using Mann–Whitney U-tests and chi-squared analyses. These results suggest that morphological
differentiation among populations from different islands has occurred over a relatively short ecological timescale,
and is likely the result of ecomorphological adaptation to differences in exploited prey hardness. Intra-island
allopatric population variation, however, was also detected in this study. Although we might expect that genetic
change is the more likely explanation for differences between islands than within, and that plasticity may be
more likely an explanation for the within- than the between-island differences, it is also possible that both
within- and between-island patterns are the results of genetic change, or of plasticity. © 2015 The Linnean
Society of London, Biological Journal of the Linnean Society, 2015, 00, 000–000.

Pacific Science, 2018

Invertebrates constitute the most diverse animal lineages on Pacific Islands, and have likewise e... more Invertebrates constitute the most diverse animal lineages on Pacific Islands, and have likewise experienced the most significant extinction rates. Recent losses of biodiversity, particularly in the form of arthropod and gastropod extinctions in the Hawaiian Islands have been driven largely by ecosystem changes brought about by loss of habitat and direct predation by introduced predators. Although Hawaii notably lacks native terrestrial reptiles and amphibians, anthropogenic releases of herpetofauna have resulted in the establishment of frogs, toads, turtles and lizards, among which are some of the most conspicuous faunal groups in the islands today (e.g. coqui frog, green day gecko, brown anole). However, despite establishment of more than two-dozen predatory reptile species in Hawaii, ecological impacts remain unknown for all but two. We have conducted surveys, collected specimens and used museum collections of the wrinkled frog, Glandirana rugosa, an established species intentionally released in the late 19th century, from three main Hawaiian Islands (Kauai, Maui, Oahu). We conducted comparative gut content analyses from two islands in an effort to assess impacts and enable prioritization of management decisions. Our results suggest that diet composition in the Hawaiian Islands is significantly different from that in its native Japan, where the dominant taxonomic groups by volume were Coleoptera (beetles), Lepidoptera (moths, butterflies) and Formicidae (ants). Invasive frogs in Hawaii exploited mostly Dermaptera (earwigs), Amphipoda (landhoppers) and Hemiptera (true bugs). In Hawaii this species also exploited endemic insects (~5% total volume, 7 genera) and snails (14 snails in 3 endemic genera).

Achatinella mustelina is a critically endangered tree snail that subsists entirely by grazing mic... more Achatinella mustelina is a critically endangered tree snail that subsists entirely by grazing microbes from leaf surfaces of native trees. Little is known about fundamental aspects of these microbe assemblages: not taxonomic composition, how this varies with host-plant or location, nor whether snails selectively consume microbes. To address these questions we collected 102 snail fecal samples as a proxy for diet, and 102 matched-leaf samples from four locations. We used Illumina amplicon sequencing to determine bacterial and fungal community composition. Microbial community structure was significantly distinct between snail feces and leaf-samples, but the same microbes occurred in both. We conclude snails are not ‘picky’ eaters at the microbial level, but graze the surface of whatever plant they are on. In a second experiment, the gut was dissected from non-endangered native tree snails in the same family as Achatinella to confirm that fecal samples reflect gut contents. Over 60% of fungal reads were shared between feces, gut and leaf samples. Overall, location, sample type (feces or leaf) and host-plant identity all significantly explained the community composition and variation among samples. Understanding the microbial ecology of microbes grazed by tree snails enables effective management when conservation requires captive breeding or field relocation.

Endangered Species Research, May 8, 2014

Journal of Herpetology

ABSTRACT.—The Jackson’s Chameleon (Trioceros jacksonii xantholophus) is a predatory, arboreal eas... more ABSTRACT.—The Jackson’s Chameleon (Trioceros jacksonii xantholophus) is a predatory, arboreal east African lizard that has become
established in the forests of several Hawaiian Islands where they have been shown to prey upon rare endemic invertebrate taxa. In this study,
we used radiotelemetry to assess movement behavior of T. j. xantholophus in three different habitats that varied in suitability for sustained
persistence of chameleons. Landscape ecology theory holds that movement behavior tends to be relatively rapid and linear in unsuitable
habitat, minimizing time spent in suboptimal areas, but more circuitous and less rapid in suitable habitat to optimize resource use. Therefore,
we predicted that in Hawaii, chameleons released in unsuitable habitat will 1) move longer distances each day; 2) follow straighter paths; 3)
move away from point of release continuously; and 4) cover larger areas, relative to those released in suitable habitat. Our results indicated that
mean daily distance, total cumulative distance, total net displacement, and home range did not vary significantly among the three habitats.
However, daily distances decreased and path tortuosity increased over time under suitable conditions, whereas the opposite pattern was seen
under unsuitable conditions. Notably, daily net displacement did not increase over time, regardless of habitat type or suitability, and home
range overlap was inversely correlated with habitat suitability. In general, Jackson’s Chameleons traveled short distances after nonlinear paths,
reflecting a sedentary life history. We 6propose that localized control and potential eradication in critical areas may be possible via manual
removal.

Abstract Here we report the first conclusive evidence of an introduced reptile (Chamaeleo jackson... more Abstract Here we report the first conclusive evidence of an introduced reptile (Chamaeleo jacksonii) feeding on Hawaiian taxa, including 11 snails in four endemic genera from two families, including four individuals of an endangered species (Achatinella mustelina), and native insects in five genera. Native Hawaiian invertebrates were discovered in the dissected stomachs of wild caught Jackson's chameleons collected from June to November 2009 on the island of Oahu.

Zoological Studies, 2023

The hydrozoan family Eirenidae is known scientifically for its morphological plasticity and chall... more The hydrozoan family Eirenidae is known scientifically for its morphological plasticity and challenges in
species identification. We used an integrative taxonomic approach based on morphological, molecular
and life history evidence to systematically assess field-collected medusae of Eirene menoni Kramp
1953 and captive raised polyps of both E. menoni and E. lacteoides Kubota and Horita 1992. Following
morphological review, we updated the genus description to include the presence of rudimentary bulbs
(warts) on the ring canal in at least eight of the 24 valid Eirene species. We propose the potential for the
mature E. menoni hydrotheca to develop into a gonotheca. However, this proposal will require additional
study for verification. We provide validated distribution records from the Indo-Pacific Ocean for E. menoni,
and updated collection records for E. lacteoides from the Yellow and East China Seas, and public
aquaria-cultured specimens from Japan and Hawaii, using cytochrome c oxidase I (COI) sequences that
we generated and compared with those from GenBank. The COI gene reliably separated four species,
each forming a monophyletic clade with strong bootstrap support and low mean intraspecific molecular
divergences (≤ 1%) within clades. However, some of the deeper nodes of the tree remained poorly
resolved, and our analysis failed to demonstrate monophyly among eirenid genera Eirene and Tima. Our
integrative taxonomic approach is essential in confirming species identity within the family Eirenidae and
genus Eirene, and we have also identified a likely range expansion of E. lacteoides to Hawaii.

Zoological Studies, 2023

The hydrozoan family Eirenidae is known scientifically for its morphological plasticity and chall... more The hydrozoan family Eirenidae is known scientifically for its morphological plasticity and challenges in species identification. We used an integrative taxonomic approach based on morphological, molecular and life history evidence to systematically assess field-collected medusae of Eirene menoni Kramp 1953 and captive raised polyps of both E. menoni and E. lacteoides Kubota and Horita 1992. Following morphological review, we updated the genus description to include the presence of rudimentary bulbs (warts) on the ring canal in at least eight of the 24 valid Eirene species. We propose the potential for the mature E. menoni hydrotheca to develop into a gonotheca, however, this will require additional study for verification. We provide validated distribution records from the Indo-Pacific Ocean for E. menoni, and updated collection records for E. lacteoides from the Yellow and East China Seas, and public aquaria-cultured specimens from Japan and Hawaii, using cytochrome c oxidase I (COI) sequences that we generated compared with those from GenBank. The COI gene reliably separated four species, each forming a monophyletic clade with strong bootstrap support and low mean intraspecific molecular divergences (≤ 1%) within clades. However, some of the deeper nodes of the tree remained poorly resolved, and our analysis failed to demonstrate monophyly among eirenid genera Eirene and Tima. Our integrative taxonomic approach is essential in confirming species identity within the family Eirenidae and genus Eirene, and we have also identified a likely range expansion of E. lacteoides to Hawaii.

Science Advances, 2022

Conspicuous social and sexual signals are predicted to experience pronounced character release wh... more Conspicuous social and sexual signals are predicted to experience pronounced character release when natural selection via predation is relaxed. However, we have few good examples of this phenomenon in the wild and none in species with dynamic color change. Here, we show that Jackson's chameleons inadvertently introduced from Kenya to Hawaii (Oahu), where there are no coevolved, native lizard predators, experienced pronounced character release of color signals. Hawaiian chameleons displayed more conspicuous social color signals than Kenyan chameleons during male contests and courtship, were less cryptic in response to bird and snake predators, and showed greater change between display and antipredator color states. Hawaiian chameleon display colors were also more conspicuous in their local than ancestral habitats, consistent with local adaptation of social signals. These results demonstrate that relaxed predation pressure can result in character release of dynamic social signals in introduced species experiencing strong sexual selection.

Journal of Coastal Science, 2021

Jellyfish stings can have substantial negative impacts on ocean recreation and tourism globally. ... more Jellyfish stings can have substantial negative impacts on ocean recreation and tourism globally. In Hawaii, where tourism
comprises a major portion of the state’s economy, the non-lethal stings of the box jellyfish, Alatina alata impact hundreds to
over one thousand Oahu beachgoers annually. Envenomated individuals may experience hypertension, cramping, and nausea
with painful dermatitis. Here we compile and summarize information based on a 25-year influx history, mass stinging events,
sting treatment costs and protocols, and socio-economic impacts on this recurrent phenomenon on the island of Oahu. We
delivered 452 questionnaires to visitors and residents at Waikiki Beach (WB) to access and quantify levels of beach user
awareness and concern regarding box jellyfish presence and stings relative to other coastal hazards. A lack of awareness of
box jellyfish and associated stings at WB was recorded in 56% of visitors and 30% of residents. Box jellyfish warning signage
was observed by only 44% of visitors and 69% of residents. Questionnaire results suggest that additional box jellyfish
communication and education are needed. Such information could be provided at beaches via permanent panels, and at hotels
via kiosks and public service announcements. These efforts to enhance public awareness could reduce both costs and time
spent by Ocean Safety and Lifeguard Services and Emergency Medical Service personnel in treating beachgoer stings.
Increased beachgoer awareness of box jellyfish would improve the WB experience and help mitigate box jellyfish stings.

Zoological Science, 2021

Tima nigroannulata sp. nov. is described from medusae collected in shallow waters of four prefect... more Tima nigroannulata sp. nov. is described from medusae collected in shallow waters of four prefectures on the Pacific coast of Japan (Miyagi, Fukushima, Kanagawa, and Miyazaki), as well as from cultures maintained at two aquaria (Enoshima Aquarium, Kanagawa Prefecture; Tsuruoka City Kamo Aquarium, Yamagata Prefecture). Adult medusae differ from those of other known species of the genus Tima Eschscholtz, 1829 in the following combination of characters: (1) umbrella usually hemispherical or higher, (2) marginal tentacles up to 50 or more in number; and (3) black pigment granules form a ring around the umbrella rim, and sometimes extend onto the tentacles and radial canals. Their hydroids, from aquarium cultures, have stolonal colonies with pedicels of varied length, vestigial hydrothecae, slender and vase-to club-shaped hydranths, and a whorl of about 20 filiform tentacles with an intertentacular web basally. Medusa buds develop singly within gonothecae that arise from the hydrothecal pedicels. The cnidomes of both hydroid and medusa stages comprise heteronemes, provisionally identified as microbasic mastigophores. Medusae of T. nigroannulata are confirmed as a unique, cohesive lineage by comparing mtDNA COI sequence fragments with those from two congeners, resulting in three well-supported reciprocally monophyletic clades, one representing each species. Records of the western Atlantic medusa Tima formosa L. Agassiz, 1862 from Japan overlap those of T. nigroannulata, and are believed to have been based on the new species described herein.

Journal of the Lepidopterists' Society 72(3):218-226. 2018 , 2018

The Mariana eight-spot butterfly (Hypolimnas octocula marianensis) and the Mariana wandering butt... more The Mariana eight-spot butterfly (Hypolimnas octocula marianensis) and the Mariana wandering butterfly (Vagrans egistina) are endemic to the Mariana Islands and both have recently been listed as federally protected under the U.S. Endangered Species Act. We conducted both targeted surveys and grid transect searches on Guam and targeted surveys across the islands of Saipan, Tinian and Rota to locate native hostplants, eggs, caterpillars and adults of these rare insects. Despite having a relatively common hostplant, V. egistina was not found during this study, even in places it had last been found. Although various life stages of H. o. marianensis were documented, the hostplants of this species were heavily impacted by grazing of introduced ungulates; only in native limestone forest with jagged tower karst topography, did hostplants persist, and the butterfly with them. The reasons for the disappearance of V. egistina are not clear, but do not appear to be related to hostplant availability. Our surveys suggest that control of invasive ungulates on Guam will be the single most effective conservation action for Mariana eight-spot recovery , and is essential to any chance of long-term persistence for the species there. H. o. marianensis has significant, unoccupied, hostplant patches on the three northern islands (Rota, Tinian, and Saipan) which might be considered as sites for future translo-cation and reintroduction efforts, in order to reduce the risk of extinction.

Although grazers have long been recognized as top–down architects of plant communities, animal ro... more Although grazers have long been recognized as top–down architects of plant communities, animal roles in determining microbial community composition have seldom been examined, particularly in aboveground systems. To determine the extent to which an animal can shape microbial communities, we conducted a controlled mesocosm study in situ to see if introducing mycophageous tree snails changed phyllosphere fungal community composition relative to matched control mesocosms. Fungal community composition and change was determined by Illumina sequencing of DNA collected from leaf surfaces before snails were introduced, daily for 3 days and weekly for 6 weeks thereafter. Scanning electron microscopy was used to confirm that grazing had occurred, and we recorded 3.5 times more cover of fungal hyphae in control mesocosms compared with those containing snails. Snails do not appear to vector novel microbes and despite grazing, a significant proportion of the initial leaf phyllosphere persisted in the mesocosms. Within-mesocosm diversities of fungi were similar regardless of whether or not snails were added. The greatest differences between the snail-treated and control mesocosms was that grazed mesocosms showed greater infiltration of microbes that were not sampled when the experiment commenced and that the variance in fungal community composition (beta diversity) was greater between leaves in snail-treated mesocosms indicating increased community heterogeneity and ecosystem fragmentation.

Ethology, Ecology & Evolution, 2018

Various aspects of social structure can be important drivers of basic behavioral patterns, includ... more Various aspects of social structure can be important drivers of basic behavioral
patterns, including dispersal, intraspecific niche partitioning, and resource
utilization. Juvenile–adult interactions such as agonistic displays and paedophagic
cannibalism can result in avoidance of adults by juveniles, and can influence
community structure via shifts in ontogenetic habitat use patterns and juvenile
dispersal. In this study, we examined the role of agonistic behavior in determining
differences in habitat utilization between life stages in an ecologically damaging
invasive lizard, Trioceros jacksonii xantholophus, in the Hawaiian Islands. We
tested the hypothesis that intraspecific aggression by adults drives observed
niche separation and juvenile dispersal. In the laboratory, we conducted paired
conspecific trials to assess paedophagic behavior, and staged contests to assess
aggression and response: 57% of adults consumed newborns when paired. In
addition, juveniles fled further, faster, and more often in response to aggressive
adult displays than from other juveniles. To assess the effect of antagonistic
behaviors on juvenile movement and its potential role in and habitat shifts, we
used radio-telemetry and exploited diet comparison to assess resource use in
juveniles versus adults. Though our results suggested no significant difference in
immature versus adult chameleon dispersal, juveniles were found to perch at
significantly lower heights above ground, and exploited different prey types than
did adults. These results suggest that resource partitioning is occurring, but the
immature chameleons are sedentary as are the adults. Due to age-dependent
habitat usage, our results suggest that T. j. xantholophus occupies a broader
niche than previously recognized. These results highlight the importance of studies
focused on patterns of behavior at different developmental stages of invasive
species, which ultimately provide better information allowing prediction of ecological
impacts and range expansion potential.

The importance of pheromones in insect and mammal social systems is well documented , but few stu... more The importance of pheromones in insect and mammal social systems is well documented , but few studies have addressed the role of pheromones in land snail behavior. In this investigation, we used a series of behavioral trials and direct analysis in real time mass spectrometry (MS) to test the hypothesis that land snails use mucous trails in orientation and chemical communication. We worked with six endemic Hawaiian land snail species in four genera, three subfamilies, and two families. We tested conspecific trail following in five of these species, and trail following occurred at a statistically significant frequency for each of the species tested (n=181, p-values ranged <0.0001–0.0494). Percentage of conspecific trials that showed trail following ranged 66.7–94.1%. None of the interspecific tests revealed evidence of trail following among species (n=105, with p-values of 0.0577–0.5000). Juvenile achatinelline snails did not follow trails of conspecific juveniles (n=30, p=0.5722) or adults (n=30, p=0.4278), nor did adults follow juvenile trails (n=30, p=0.5722). Comparative MS analysis of adult and juvenile trails showed distinct chemical signatures in the two groups. Signals corresponding to medium-and long-chain fatty acids and other unidentified small molecules were present in adult but not in juvenile trails. Considered together, these results support the hypotheses that trail following could serve an important social and reproductive function. This discovery provides evidence for the presence of an ephemeral tree snail pheromone, which could have important implications for the conservation of these increasingly rare and threatened species.

Invasive reptiles cause global ecosystem damage and are difficult to control once established. Vi... more Invasive reptiles cause global ecosystem damage and are difficult to control once established. Visual detection and manual capture are time consuming and largely ineffective at eradication, particularly for cryptic species. The Jackson's chameleon (Trioceros jacksonii xantholophus), native to eastern Africa, is popular in the global pet trade and has become established in several localities, including the Hawaiian Islands where it has escaped or been intentionally released into sensitive native forest habitat where it feeds on endangered species. Here we tested an orally delivered, chemical toxicant as a feasible management technique for this invasive lizard in Hawaii. We administered predetermined dosages of powdered acetaminophen to adult chamleoens and determined that the dosage necessary to achieve 95% mortality within 48 h across size classes was 2000 mg/kg, or 90 mg of acetaminophen for an adult average mass of 45 g. Since the liver is known to process acetaminophen in vertebrate taxa, we conducted post mortem histological examination of liver tissue for all specimens at the 48 h time point. Finally, we propose a testable mechanism for field delivery of this oral toxicant following behavioral trials.

Although grazers have long been recognized as top–down architects of plant communities, animal ro... more Although grazers have long been recognized as top–down architects of plant communities, animal roles in determining microbial community composition have seldom been examined, particularly in aboveground systems. To determine the extent to which an animal can shape microbial communities, we conducted a controlled mesocosm study in situ to see if introducing mycophageous tree snails changed phyllosphere fungal community composition relative to matched control mesocosms. Fungal community composition and change was determined by Illumina sequencing of DNA collected from leaf surfaces before snails were introduced, daily for 3 days and weekly for 6 weeks thereafter. Scanning electron microscopy was used to confirm that grazing had occurred, and we recorded 3.5 times more cover of fungal hyphae in control mesocosms compared with those containing snails. Snails do not appear to vector novel microbes and despite grazing, a significant proportion of the initial leaf phyllosphere persisted in the mesocosms. Within-mesocosm diversities of fungi were similar regardless of whether or not snails were added. The greatest differences between the snail-treated and control mesocosms was that grazed mesocosms showed greater infiltration of microbes that were not sampled when the experiment commenced and that the variance in fungal community composition (beta diversity) was greater between leaves in snail-treated mesocosms indicating increased community heterogeneity and ecosystem fragmentation.

Hawaii’s diverse achatinellid tree snails occur almost exclusively in host trees and shrubs that ... more Hawaii’s diverse achatinellid tree snails occur almost exclusively in host trees and shrubs that are native to the Hawaiian Archipelago. A few exceptions to this pattern are known, where an arboreal gastropod population has persisted in introduced plants. On Oahu, Hawaii, the last known population of the single island endemic snail Auriculella diaphana has persisted in nonnative plants for multiple decades, leading to the following question: are there differences in relative fitness of native gastropods in native versus nonnative host plants? To address this we conducted laboratory trials with A. diaphana in three treatment groups, one with the two dominant nonnative host plants from their current distribution, another group with two known primary native host plant species, and a third treatment maintained in cages with a mixture of equal parts nonnative and native plants. Trials were conducted over two 16-week intervals, with 100 snails. Relative fitness was assessed among treatments as survival and reproductive output (number of eggs produced). Results demonstrated that while survival of adult snails was equivalent across treatments (100%), fecundity was significantly higher in cages where native plants were available. Egg production was 20.05-fold and 14.95-fold greater in treatments with 100% and 50% native host plants, respectively, than in treatments with nonnative plants only. These results suggest that native snails persisting in nonnative host plants experience sublethal stress, reflected in a dramatic reduction in reproductive output. Snails in treatments with mixed native and nonnative plants also showed significantly higher reproduction than in nonnative plant cages. We suggest that the observed decreased fecundity is due to diminished nutritional value of the phyllosphere of nonnative vegetation, and that translocation of this and related species occurring in nonnative habitat, to nearby native host plants will be beneficial in terms of relative fitness.

Key Words: Auriculella diaphana, Hawaiian tree snails, biological conservation, native Hawaiian species, ecosystem restoration, relative fitness, resource management, snail reproduction.

Endangered species can be safeguarded against extinction by raising subpopulations in ex situ fac... more Endangered species can be safeguarded against extinction by raising subpopulations in ex situ facilities that mimic their wild habitats. This is difficult when the endangered animal’s diet is cryptic. We present a combined molecular and behavioral approach to assess the ex situ diet of Achatinella a critically endangered genus of tree snail, to determine how diet of captive snails differs from wild snails. Ex situ snails are currently fed biofilms growing on the surface of leaves, as well as a cultured fungus isolated from this same habitat. Amplicon sequencing of DNA extracted from feces of cultured snails confirms that this cultured fungus is abundant in the wild, but that it dominates the diet of the ex situ snail diet (comprising ~38% of sequences). The diet of captive snails is significantly less diverse compared to wild snails. To test the hypothesis that snails have diet preferences, we conducted feeding trials. These used a surrogate snail species, Auriculella diaphana, which is a confamilial Oahu endemic, though non-­‐federally listed. Contrary to our expectations we found that snails do have feeding preferences. Furthermore, our feeding preference trials show that over all other feeding options snails most preferred the “no-­‐microbe” control, which consisted only of potato dextrose agar (PDA). PDA is rich in simple carbohydrates, in contrast to the oligotrophic environment of wild tree-­‐snails. These results suggest further research should focus on calorie budgets of snails and on devising new approaches to supplementing their ex situ diet.

Biological invasions are recognized as a primary driver of large-scale changes in global ecosyste... more Biological invasions are recognized as a primary driver of large-scale changes in global ecosystems. This study
addresses ecomorphological variation in head size within and among populations of an ecologically destructive
invasive predator, and evaluates the potential roles of environmental components in phenotypic differentiation.
We used four size-corrected measurements of head morphology in Jackson’s chameleons, Trioceros jacksonii
xantholophus (N = 319), collected from multiple Hawaiian Islands to assess phenotypic variation among and
within islands. Results of analysis of variance (ANOVA) comparing chameleon head size (PC1) among islands
revealed significant differences (mean difference > 5%) associated with variation in both rainfall and diet
composition using Mann–Whitney U-tests and chi-squared analyses. These results suggest that morphological
differentiation among populations from different islands has occurred over a relatively short ecological timescale,
and is likely the result of ecomorphological adaptation to differences in exploited prey hardness. Intra-island
allopatric population variation, however, was also detected in this study. Although we might expect that genetic
change is the more likely explanation for differences between islands than within, and that plasticity may be
more likely an explanation for the within- than the between-island differences, it is also possible that both
within- and between-island patterns are the results of genetic change, or of plasticity. © 2015 The Linnean
Society of London, Biological Journal of the Linnean Society, 2015, 00, 000–000.

Pacific Science, 2018

Invertebrates constitute the most diverse animal lineages on Pacific Islands, and have likewise e... more Invertebrates constitute the most diverse animal lineages on Pacific Islands, and have likewise experienced the most significant extinction rates. Recent losses of biodiversity, particularly in the form of arthropod and gastropod extinctions in the Hawaiian Islands have been driven largely by ecosystem changes brought about by loss of habitat and direct predation by introduced predators. Although Hawaii notably lacks native terrestrial reptiles and amphibians, anthropogenic releases of herpetofauna have resulted in the establishment of frogs, toads, turtles and lizards, among which are some of the most conspicuous faunal groups in the islands today (e.g. coqui frog, green day gecko, brown anole). However, despite establishment of more than two-dozen predatory reptile species in Hawaii, ecological impacts remain unknown for all but two. We have conducted surveys, collected specimens and used museum collections of the wrinkled frog, Glandirana rugosa, an established species intentionally released in the late 19th century, from three main Hawaiian Islands (Kauai, Maui, Oahu). We conducted comparative gut content analyses from two islands in an effort to assess impacts and enable prioritization of management decisions. Our results suggest that diet composition in the Hawaiian Islands is significantly different from that in its native Japan, where the dominant taxonomic groups by volume were Coleoptera (beetles), Lepidoptera (moths, butterflies) and Formicidae (ants). Invasive frogs in Hawaii exploited mostly Dermaptera (earwigs), Amphipoda (landhoppers) and Hemiptera (true bugs). In Hawaii this species also exploited endemic insects (~5% total volume, 7 genera) and snails (14 snails in 3 endemic genera).

Achatinella mustelina is a critically endangered tree snail that subsists entirely by grazing mic... more Achatinella mustelina is a critically endangered tree snail that subsists entirely by grazing microbes from leaf surfaces of native trees. Little is known about fundamental aspects of these microbe assemblages: not taxonomic composition, how this varies with host-plant or location, nor whether snails selectively consume microbes. To address these questions we collected 102 snail fecal samples as a proxy for diet, and 102 matched-leaf samples from four locations. We used Illumina amplicon sequencing to determine bacterial and fungal community composition. Microbial community structure was significantly distinct between snail feces and leaf-samples, but the same microbes occurred in both. We conclude snails are not ‘picky’ eaters at the microbial level, but graze the surface of whatever plant they are on. In a second experiment, the gut was dissected from non-endangered native tree snails in the same family as Achatinella to confirm that fecal samples reflect gut contents. Over 60% of fungal reads were shared between feces, gut and leaf samples. Overall, location, sample type (feces or leaf) and host-plant identity all significantly explained the community composition and variation among samples. Understanding the microbial ecology of microbes grazed by tree snails enables effective management when conservation requires captive breeding or field relocation.

Endangered Species Research, May 8, 2014

Journal of Herpetology

ABSTRACT.—The Jackson’s Chameleon (Trioceros jacksonii xantholophus) is a predatory, arboreal eas... more ABSTRACT.—The Jackson’s Chameleon (Trioceros jacksonii xantholophus) is a predatory, arboreal east African lizard that has become
established in the forests of several Hawaiian Islands where they have been shown to prey upon rare endemic invertebrate taxa. In this study,
we used radiotelemetry to assess movement behavior of T. j. xantholophus in three different habitats that varied in suitability for sustained
persistence of chameleons. Landscape ecology theory holds that movement behavior tends to be relatively rapid and linear in unsuitable
habitat, minimizing time spent in suboptimal areas, but more circuitous and less rapid in suitable habitat to optimize resource use. Therefore,
we predicted that in Hawaii, chameleons released in unsuitable habitat will 1) move longer distances each day; 2) follow straighter paths; 3)
move away from point of release continuously; and 4) cover larger areas, relative to those released in suitable habitat. Our results indicated that
mean daily distance, total cumulative distance, total net displacement, and home range did not vary significantly among the three habitats.
However, daily distances decreased and path tortuosity increased over time under suitable conditions, whereas the opposite pattern was seen
under unsuitable conditions. Notably, daily net displacement did not increase over time, regardless of habitat type or suitability, and home
range overlap was inversely correlated with habitat suitability. In general, Jackson’s Chameleons traveled short distances after nonlinear paths,
reflecting a sedentary life history. We 6propose that localized control and potential eradication in critical areas may be possible via manual
removal.

Abstract Here we report the first conclusive evidence of an introduced reptile (Chamaeleo jackson... more Abstract Here we report the first conclusive evidence of an introduced reptile (Chamaeleo jacksonii) feeding on Hawaiian taxa, including 11 snails in four endemic genera from two families, including four individuals of an endangered species (Achatinella mustelina), and native insects in five genera. Native Hawaiian invertebrates were discovered in the dissected stomachs of wild caught Jackson's chameleons collected from June to November 2009 on the island of Oahu.

PubMed, Dec 31, 2022

The hydrozoan family Eirenidae is known scientifically for its morphological plasticity and chall... more The hydrozoan family Eirenidae is known scientifically for its morphological plasticity and challenges in species identification. We used an integrative taxonomic approach based on morphological, molecular and life history evidence to systematically assess field-collected medusae of Eirene menoni Kramp 1953 and captive raised polyps of both E. menoni and E. lacteoides Kubota and Horita 1992. Following morphological review, we updated the genus description to include the presence of rudimentary bulbs (warts) on the ring canal in at least eight of the 24 valid Eirene species. We propose the potential for the mature E. menoni hydrotheca to develop into a gonotheca. However, this proposal will require additional study for verification. We provide validated distribution records from the Indo-Pacific Ocean for E. menoni,and updated collection records for E. lacteoides from the Yellow and East China Seas, and public aquaria-cultured specimens from Japan and Hawaii, using cytochrome c oxidase I (COI) sequences that we generated and compared with those from GenBank. The COI gene reliably separated four species, each forming a monophyletic clade with strong bootstrap support and low mean intraspecific molecular divergences (≤ 1%) within clades. However, some of the deeper nodes of the tree remained poorly resolved, and our analysis failed to demonstrate monophyly among eirenid genera Eirene and Tima. Our integrative taxonomic approach is essential in confirming species identity within the family Eirenidae and genus Eirene,and we have also identified a likely range expansion of E. lacteoides to Hawaii.

Journal of the Lepidopterists' Society, 2018

DOAJ (DOAJ: Directory of Open Access Journals), Dec 1, 2012

DOAJ (DOAJ: Directory of Open Access Journals), Dec 1, 2012

Philosophical Transactions of the Royal Society B, Sep 2, 2008

Molecular Ecology, Jul 11, 2007

University of California Press eBooks, Dec 31, 2019

Systematic Biology, Dec 1, 2005

Frontiers of biogeography, Dec 31, 2012

Journal of Herpetology, Dec 1, 2014

Biodiversity and Conservation, Dec 25, 2009

Molecular Phylogenetics and Evolution, Apr 1, 2004

Molecular Ecology, Mar 1, 2002

Proceedings of the Hawaiian Entomological Society, Dec 1, 2008

Science Advances, May 13, 2022

Molecular Phylogenetics and Evolution, Aug 1, 2004

University of Hawaii Press eBooks, Dec 31, 2017

3 Contributions of Ex Situ Propagation and Molecular Genetics to Conservation of Hawaiian Tree Sn... more 3 Contributions of Ex Situ Propagation and Molecular Genetics to Conservation of Hawaiian Tree Snails Michael G. Hadfield, Brenden S. Holland ... it grew from around 40 snails to about 120 (population sizes estimated by the Manly–Parr multiple-recapture method; Begon 1979). ...

Manual removal of invasive species is largely ineffective in decreasing population densities, par... more Manual removal of invasive species is largely ineffective in decreasing population densities, particularly for cryptic taxa. The Jackson’s chameleon (Trioceros jacksonii xantholophus), native to eastern Africa, is popular in the global pet trade and has become established in several global localities, including the Hawaiian Islands, where it is currently established and continues to expand its range. Based on preliminary success of field trials aimed at control of the invasive brown tree snake on Guam, we tested the toxicity of acetaminophen using predetermined dosages of the drug at 200, 400, 800, 1,600, and 2,000 mg/kg, in adult chameleons (n=4-8 individuals per treatment; chameleon body mass ranged from 15 - 60 g). The minimum dosage to achieve ≥95% mortality within 48 hours was 2,000 mg/kg, or 90 mg of acetaminophen for an average adult chameleon of 45 g. Since the liver is known to process acetaminophen in vertebrate taxa, we conducted histological examination of liver tissue for all specimens at the 48-hour time point. Finally we propose a testable mechanism for field delivery of this oral toxicant.

Although the diverse and colorful Hawaiian tree snails have been studied for many decades, the po... more Although the diverse and colorful Hawaiian tree snails have been studied for many decades, the potential ecological role played by tree snails has only been the subject of speculation, and has never been scientifically addressed. We've recently confirmed that these arboreal snails graze on microbial biofilms that grow on host tree leaves, depositing feces, which wash down to the forest floor in frequent rain showers. Could this provide important natural fertilizer for the trees themselves?