Ingrid Spies - Academia.edu (original) (raw)
Papers by Ingrid Spies
Marine Ecology Progress Series
Several new species of oviparous skates of the genus Bathyraja have been identified over the past... more Several new species of oviparous skates of the genus Bathyraja have been identified over the past 2 decades, yet it is possible that a complete understanding of species diversity among this group has not been achieved. We used genetics and morphology to screen for the presence of species-level differentiation among embryos from nursery areas in the eastern Bering Sea that were initially identified as the Alaska skate B. parmifera. A sample of 57 embryos from Pervenets Canyon differed significantly at single nucleotide polymorphism loci from 297 other B. parmifera samples, and differences were on the order of those observed between B. parmifera and the leopard skate B. panthera. This sample of embryos was similar to B. parmifera at the cytochrome c oxidase subunit I (COI) mitochondrial locus. We discuss whether this group of embryos may represent an undescribed cryptic species. Although morphological description of adults is required for a complete species description, only embryo sa...
BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.
Genetic population structure of Pacific cod, Gadus macrocephalus, was examined across much of its... more Genetic population structure of Pacific cod, Gadus macrocephalus, was examined across much of its northeastern Pacific range by screening variation at 11 microsatellite DNA loci. Estimates of FST (0.005 ± 0.002) and RST (0.010 ± 0.003) over all samples suggested that effective dispersal is limited among populations. Genetic divergence was highly correlated with geographic distance in an isolation-by-distance (IBD) pattern along the entire coastal continuum in the northeastern Pacific Ocean (~4000 km; r 2 = 0.83), extending from Washington State to the Aleutian Islands, and over smaller geographic distances for three locations in Alaska (~1700 km; r 2 = 0.56). Slopes of IBD regressions suggested average dispersal distance between birth and reproduction of less than 30 km. Exceptions to this pattern were found in samples taken from fjord environments in the Georgia Basin (the Strait of Georgia (Canada) and Puget Sound (USA)), where populations were differentiated from coastal cod. Our results showed population structure at spatial scales relevant to fisheries management, both caused by limited dispersal along the coast and by sharp barriers to migration isolating smaller stocks in coastal fjord environments. Résumé : Nous avons examiné la structure génétique de la population des morues du Pacifique, Gadus macrocephalus, dans presque toute son aire de répartition dans le nord-est du Pacifique, par la détermination de la variation à 11 locus microsatellites d'ADN. Les valeurs estimées de F ST (0,005 ± 0,002) et R ST (0,010 ± 0,003) pour l'ensemble des échantillons laissent penser que la dispersion entre les populations est limitée. Il y a une forte corrélation entre la divergence génétique et la distance géographique selon un patron d'isolement par la distance (IBD) sur l'ensemble du continuum côtier dans le nord-est du Pacifique (~4000 km; r 2 = 0,83), depuis l'état de Washington aux îles Aléoutiennes, ainsi que sur des distances plus courtes dans trois sites d'Alaska (~700 km; r 2 = 0,56). Les pentes des régressions d'IBD indiquent que la distance moyenne de dispersion de la naissance à la reproduction est inférieure à 30 km. Des exceptions à ces patrons se retrouvent dans les échantillons provenant des environnements de fjords dans le bassin de Géorgie, soit le détroit de Géorgie (Canada) et Puget Sound (É .-U.), où les populations se différencient des morues de la côte. Nos résultats présentent une structure de population à des échelles qui sont d'intérêt pour la gestion des pêches, causée à la fois par une dispersion restreinte le long de la côte et par d'importantes barrières à la migration qui isolent les stocks plus petits dans les environnements des fjords côtiers.
The mating system and patterns of gender-specific egg cannibalism in Atka mackerel, Pleurogrammus... more The mating system and patterns of gender-specific egg cannibalism in Atka mackerel, Pleurogrammus monopterygius, were examined through genetic parentage analysis of embryos in egg masses produced in captive and wild populations. Parentage analysis of egg masses produced by a captive population in a small exhibit tank revealed that 38% of the egg masses contained contributions by nonnest attendant males. In contrast, all egg masses produced in a large exhibit tank resulted from monogamous matings of females with resident nest-tending males, suggesting density-dependence of sneaked fertilizations. Females appeared to mate randomly with two nest-tending males in the large exhibit tank at the Alaska SeaLife Center. Multiple parentage was detected in 35% of the egg masses collected in the field or retrieved from the stomachs of adult cannibals. Half-sib and unrelated full-sib families were found in several fused egg masses, indicating that the reproductive output from multiple males and females may be combined sequentially in a single egg mass and that nest-attendant males may abandon or be excluded from their territory during the spawning season. Analysis of loose eggs and partial egg masses ingested by four female and 15 male cannibals showed that nearly all conspecific predation represented heterocannibalism. One instance of partial filial cannibalism was detected in a male who was one of multiple sires for that egg mass. The significance of mating and cannibalistic behaviors influenced by sexual selection in fish species with exclusive paternal care is discussed, especially with respect to other greenling species.
Proceedings of the National Academy of Sciences of the United States of America, May 8, 2018
Genetic data are commonly used to estimate connectivity between putative populations, but transla... more Genetic data are commonly used to estimate connectivity between putative populations, but translating them to demographic dispersal rates is complicated. Theoretical equations that infer a migration rate based on the genetic estimator , such as Wright's equation, ≈ 1/(4 + 1), make assumptions that do not apply to most real populations. How complexities inherent to real populations affect migration was exemplified by Atlantic cod in the North Sea and Skagerrak and was examined within an age-structured model that incorporated genetic markers. Migration was determined under various scenarios by varying the number of simulated migrants until the mean simulated level of genetic differentiation matched a fixed level of genetic differentiation equal to empirical estimates. Parameters that decreased the / ratio (where is the effective and is the total population size), such as high fishing mortality and high fishing gear selectivity, increased the number of migrants required to achieve ...
Marine and Coastal Fisheries
The Aleutian Islands ecosystem is a highly dynamic marine environment that supports commercially ... more The Aleutian Islands ecosystem is a highly dynamic marine environment that supports commercially important fish species, such as Atka Mackerel Pleurogrammus monopterygius and Northern Rockfish Sebastes polyspinis, and several large marine mammals, including the Steller sea lion (SSL) Eumetopias jubatus. To protect SSL foraging behavior and prey, trawl exclusion zones (TEZs) were established around SSL rookeries and haulouts across the Aleutian Islands and are closed to bottom trawling. The Atka Mackerel fishery is concentrated at small, local patches (~37.04 km [~20 nautical miles]) across the Aleutian Islands, often near and adjacent to TEZs. Food web models and fishery stock assessments predict sufficient prey for both the fishery and foraging SSLs at the level of large management areas (each area is~463 km [~250 nautical miles] longitudinally), but little is known about local fish distribution (~37.04 km) in proximity to SSL rookeries and haulouts. We used CPUE to examine the spatial distribution of two SSL prey species (Atka Mackerel and Northern Rockfish) and marine invertebrates (as a proxy for habitat quality)
Marine and Coastal Fisheries, 2011
in fish with differing growth patterns. Spawning biomass is often used as a proxy for reproductiv... more in fish with differing growth patterns. Spawning biomass is often used as a proxy for reproductive potential on the assumption that fecundity is directly proportional to body weight. We examined variations in the reproductive potential of Atka mackerel Pleurogrammus monopterygius by studying the effect of differential growth and condition patterns on fecundity, atresia, and egg energy. Fecundity and egg energy were determined for fish from two geographic areas, Seguam Pass and Amchitka Island, Alaska, and compared with those of fish held in captivity. These Atka mackerel showed distinct differences in growth and condition, with weight at length and length at age being the highest among captive fish, intermediate among fish from Seguam Pass, and lowest among fish from Amchitka Island. Realized fecundity showed that on average captive fish spawned seven batches, fish from Seguam Pass six batches, and fish from Amchitka Island five batches. For wild fish, potential and realized fecundity at length or age was significantly higher at Seguam Pass than at Amchitka Island, whereas the fecundity-at-weight relationship did not differ by area, suggesting that weight is a better predictor of fecundity than length or age. Atresia and batch fecundity by length or weight did not differ by area, suggesting that the variation in fecundity is better explained by the variation in batch number than by batch size. Oocyte dry weight was higher for captive fish than for wild fish, whereas batch order did not significantly affect oocyte dry weight. Increased potential fecundity, realized fecundity, and oocyte quality in Atka mackerel females were strongly related to body size, indicating that growth differences and maternal feeding success impact the fecundity and oocyte quality of Atka mackerel. Therefore, changes in growth and condition patterns need to be taken into account to accurately estimate the reproductive potential of this species. management and life history theory as a measure of reproductive potential based on the usually strong correlation between population fecundity and spawning biomass. The fecundity of fish populations has been demonstrated to vary between areas 324 Downloaded by [University of Alaska Fairbanks] at 05
Marine Ecology Progress Series
Several new species of oviparous skates of the genus Bathyraja have been identified over the past... more Several new species of oviparous skates of the genus Bathyraja have been identified over the past 2 decades, yet it is possible that a complete understanding of species diversity among this group has not been achieved. We used genetics and morphology to screen for the presence of species-level differentiation among embryos from nursery areas in the eastern Bering Sea that were initially identified as the Alaska skate B. parmifera. A sample of 57 embryos from Pervenets Canyon differed significantly at single nucleotide polymorphism loci from 297 other B. parmifera samples, and differences were on the order of those observed between B. parmifera and the leopard skate B. panthera. This sample of embryos was similar to B. parmifera at the cytochrome c oxidase subunit I (COI) mitochondrial locus. We discuss whether this group of embryos may represent an undescribed cryptic species. Although morphological description of adults is required for a complete species description, only embryo sa...
BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.
Genetic population structure of Pacific cod, Gadus macrocephalus, was examined across much of its... more Genetic population structure of Pacific cod, Gadus macrocephalus, was examined across much of its northeastern Pacific range by screening variation at 11 microsatellite DNA loci. Estimates of FST (0.005 ± 0.002) and RST (0.010 ± 0.003) over all samples suggested that effective dispersal is limited among populations. Genetic divergence was highly correlated with geographic distance in an isolation-by-distance (IBD) pattern along the entire coastal continuum in the northeastern Pacific Ocean (~4000 km; r 2 = 0.83), extending from Washington State to the Aleutian Islands, and over smaller geographic distances for three locations in Alaska (~1700 km; r 2 = 0.56). Slopes of IBD regressions suggested average dispersal distance between birth and reproduction of less than 30 km. Exceptions to this pattern were found in samples taken from fjord environments in the Georgia Basin (the Strait of Georgia (Canada) and Puget Sound (USA)), where populations were differentiated from coastal cod. Our results showed population structure at spatial scales relevant to fisheries management, both caused by limited dispersal along the coast and by sharp barriers to migration isolating smaller stocks in coastal fjord environments. Résumé : Nous avons examiné la structure génétique de la population des morues du Pacifique, Gadus macrocephalus, dans presque toute son aire de répartition dans le nord-est du Pacifique, par la détermination de la variation à 11 locus microsatellites d'ADN. Les valeurs estimées de F ST (0,005 ± 0,002) et R ST (0,010 ± 0,003) pour l'ensemble des échantillons laissent penser que la dispersion entre les populations est limitée. Il y a une forte corrélation entre la divergence génétique et la distance géographique selon un patron d'isolement par la distance (IBD) sur l'ensemble du continuum côtier dans le nord-est du Pacifique (~4000 km; r 2 = 0,83), depuis l'état de Washington aux îles Aléoutiennes, ainsi que sur des distances plus courtes dans trois sites d'Alaska (~700 km; r 2 = 0,56). Les pentes des régressions d'IBD indiquent que la distance moyenne de dispersion de la naissance à la reproduction est inférieure à 30 km. Des exceptions à ces patrons se retrouvent dans les échantillons provenant des environnements de fjords dans le bassin de Géorgie, soit le détroit de Géorgie (Canada) et Puget Sound (É .-U.), où les populations se différencient des morues de la côte. Nos résultats présentent une structure de population à des échelles qui sont d'intérêt pour la gestion des pêches, causée à la fois par une dispersion restreinte le long de la côte et par d'importantes barrières à la migration qui isolent les stocks plus petits dans les environnements des fjords côtiers.
The mating system and patterns of gender-specific egg cannibalism in Atka mackerel, Pleurogrammus... more The mating system and patterns of gender-specific egg cannibalism in Atka mackerel, Pleurogrammus monopterygius, were examined through genetic parentage analysis of embryos in egg masses produced in captive and wild populations. Parentage analysis of egg masses produced by a captive population in a small exhibit tank revealed that 38% of the egg masses contained contributions by nonnest attendant males. In contrast, all egg masses produced in a large exhibit tank resulted from monogamous matings of females with resident nest-tending males, suggesting density-dependence of sneaked fertilizations. Females appeared to mate randomly with two nest-tending males in the large exhibit tank at the Alaska SeaLife Center. Multiple parentage was detected in 35% of the egg masses collected in the field or retrieved from the stomachs of adult cannibals. Half-sib and unrelated full-sib families were found in several fused egg masses, indicating that the reproductive output from multiple males and females may be combined sequentially in a single egg mass and that nest-attendant males may abandon or be excluded from their territory during the spawning season. Analysis of loose eggs and partial egg masses ingested by four female and 15 male cannibals showed that nearly all conspecific predation represented heterocannibalism. One instance of partial filial cannibalism was detected in a male who was one of multiple sires for that egg mass. The significance of mating and cannibalistic behaviors influenced by sexual selection in fish species with exclusive paternal care is discussed, especially with respect to other greenling species.
Proceedings of the National Academy of Sciences of the United States of America, May 8, 2018
Genetic data are commonly used to estimate connectivity between putative populations, but transla... more Genetic data are commonly used to estimate connectivity between putative populations, but translating them to demographic dispersal rates is complicated. Theoretical equations that infer a migration rate based on the genetic estimator , such as Wright's equation, ≈ 1/(4 + 1), make assumptions that do not apply to most real populations. How complexities inherent to real populations affect migration was exemplified by Atlantic cod in the North Sea and Skagerrak and was examined within an age-structured model that incorporated genetic markers. Migration was determined under various scenarios by varying the number of simulated migrants until the mean simulated level of genetic differentiation matched a fixed level of genetic differentiation equal to empirical estimates. Parameters that decreased the / ratio (where is the effective and is the total population size), such as high fishing mortality and high fishing gear selectivity, increased the number of migrants required to achieve ...
Marine and Coastal Fisheries
The Aleutian Islands ecosystem is a highly dynamic marine environment that supports commercially ... more The Aleutian Islands ecosystem is a highly dynamic marine environment that supports commercially important fish species, such as Atka Mackerel Pleurogrammus monopterygius and Northern Rockfish Sebastes polyspinis, and several large marine mammals, including the Steller sea lion (SSL) Eumetopias jubatus. To protect SSL foraging behavior and prey, trawl exclusion zones (TEZs) were established around SSL rookeries and haulouts across the Aleutian Islands and are closed to bottom trawling. The Atka Mackerel fishery is concentrated at small, local patches (~37.04 km [~20 nautical miles]) across the Aleutian Islands, often near and adjacent to TEZs. Food web models and fishery stock assessments predict sufficient prey for both the fishery and foraging SSLs at the level of large management areas (each area is~463 km [~250 nautical miles] longitudinally), but little is known about local fish distribution (~37.04 km) in proximity to SSL rookeries and haulouts. We used CPUE to examine the spatial distribution of two SSL prey species (Atka Mackerel and Northern Rockfish) and marine invertebrates (as a proxy for habitat quality)
Marine and Coastal Fisheries, 2011
in fish with differing growth patterns. Spawning biomass is often used as a proxy for reproductiv... more in fish with differing growth patterns. Spawning biomass is often used as a proxy for reproductive potential on the assumption that fecundity is directly proportional to body weight. We examined variations in the reproductive potential of Atka mackerel Pleurogrammus monopterygius by studying the effect of differential growth and condition patterns on fecundity, atresia, and egg energy. Fecundity and egg energy were determined for fish from two geographic areas, Seguam Pass and Amchitka Island, Alaska, and compared with those of fish held in captivity. These Atka mackerel showed distinct differences in growth and condition, with weight at length and length at age being the highest among captive fish, intermediate among fish from Seguam Pass, and lowest among fish from Amchitka Island. Realized fecundity showed that on average captive fish spawned seven batches, fish from Seguam Pass six batches, and fish from Amchitka Island five batches. For wild fish, potential and realized fecundity at length or age was significantly higher at Seguam Pass than at Amchitka Island, whereas the fecundity-at-weight relationship did not differ by area, suggesting that weight is a better predictor of fecundity than length or age. Atresia and batch fecundity by length or weight did not differ by area, suggesting that the variation in fecundity is better explained by the variation in batch number than by batch size. Oocyte dry weight was higher for captive fish than for wild fish, whereas batch order did not significantly affect oocyte dry weight. Increased potential fecundity, realized fecundity, and oocyte quality in Atka mackerel females were strongly related to body size, indicating that growth differences and maternal feeding success impact the fecundity and oocyte quality of Atka mackerel. Therefore, changes in growth and condition patterns need to be taken into account to accurately estimate the reproductive potential of this species. management and life history theory as a measure of reproductive potential based on the usually strong correlation between population fecundity and spawning biomass. The fecundity of fish populations has been demonstrated to vary between areas 324 Downloaded by [University of Alaska Fairbanks] at 05