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Frontiers in Marine Science
Loggerhead turtles are a globally vulnerable species of marine turtle. Broad-scale patterns of di... more Loggerhead turtles are a globally vulnerable species of marine turtle. Broad-scale patterns of distribution and abundance can provide regional managers a tool to effectively conserve and manage this species at basin and sub-basin scales. In this study, combined aerial and shipboard line transect survey data collected between 2003 and 2018 were used to estimate distribution and abundance throughout the Mediterranean Sea. Approximately 230,000 linear kilometers of survey effort, from seven different surveying organizations were incorporated into a generalized additive model to relate loggerhead density on survey segments to environmental conditions. Two spatial density models estimating loggerhead density, abundance, and distribution were generated – one a long-term annual average covering 2003-2018 and another covering the summer of 2018, when a basin-wide aerial survey, the Agreement on the Conservation of Cetaceans of the Black Sea, Mediterranean Sea and Contiguous Atlantic Area Su...
Animals, 2022
Chlamydiae are obligate intracellular bacteria that include pathogens of human and veterinary imp... more Chlamydiae are obligate intracellular bacteria that include pathogens of human and veterinary importance. Several reptiles were reported to host chlamydial agents, but pathogenicity in these animals still needs clarification. Given that only one report of chlamydiosis was described in sea turtles, and that chlamydiae might also be detected in hosts without clinical signs, the current study examined asymptomatic Mediterranean loggerhead sea turtles for the presence of chlamydial DNA. Twenty loggerhead sea turtles, rehabilitated at the Marine Turtle Research Centre (Portici, Italy), were examined collecting ocular-conjunctival, oropharyngeal and nasal swabs. Samples were processed through quantitative and conventional PCR analyses to identify Chlamydiales and Chlamydiaceae, with particular attention to C. pecorum, C. pneumoniae, C. psittaci, and C. trachomatis. Although it was not possible to determine the species of chlamydiae involved, the detection of chlamydial DNA from the collec...
Diversity and Distributions, 2022
Endangered Species Research, 2016
Marine Ecology Progress Series, 1999
Marine Ecology Progress Series, 2007
Marine Ecology Progress Series, 2000
Marine Ecology Progress Series, 2012
Marine Ecology Progress Series, 1999
Physiological and Biochemical Zoology, 2004
BMC Veterinary Research
Background: Caretta caretta is the most abundant sea turtle species in the Mediterranean, and stu... more Background: Caretta caretta is the most abundant sea turtle species in the Mediterranean, and studies on this species have vastly expanded during recent years, including those investigating gut bacterial and parasitic communities. Members of these communities have been reported with variable prevalence and pathogenicity, mainly depending on their host and environment (e.g. lifespan, distribution, habitat, diet, health status and stressors). Indeed, many species commonly inhabiting the sea turtle gastrointestinal tract exhibit an opportunistic behaviour. This study aimed to provide baseline data on enterobacterial and parasitic composition, through bacteriological culture-based methods and the FLOTAC parasitological technique, in cloacal and faecal samples of 30 live Caretta caretta, examined upon their arrival at the Marine Turtle Research Centre (Portici, Italy). Results: Enterobacteriaceae were isolated in 18/23 cloacal samples (78.3%), with Citrobacter and Morganella as the most common genera, followed by Proteus, Enterobacter, Providencia, and Hafnia. Parasitic elements were detected in 11/30 faecal samples (36.7%), with Enodiotrema, Rhytidodes, and Eimeria as most common genera, followed by Pachypsolus and Cymatocarpus. Additionally, Angiodyctium is reported for the first time in this host. The majority (47.8%) of sea turtles hosted exclusively Enterobacteriaceae, whereas 30.4% hosted both parasites and Enterobacteriaceae; the remaining 21.8% hosted neither of the agents. Conclusions: Bacteria and parasites evaluated in the present study are common in Mediterranean loggerhead sea turtles, with slight differences between the western and eastern basin. Although naturally present in the gastrointestinal system of free-living sea turtles, their relationship with these hosts might range from mutualism to parasitism. Indeed, members of the gut community might express their pathogenic potential in immune-compromised animals, such as those in rehabilitation facilities. Therefore, it is advisable to include in the standard work-up of rescued sea turtles a screening procedure for such opportunistic agents, in order to better evaluate the animal's health status and achieve timely intervention with appropriate treatment, thus improving rehabilitation. Furthermore, data collected from free-living sea turtles represent a starting point for investigating wild populations. However, further studies are needed to clarify the differences between sea turtle's normal gut microbiome and pathobiome.
Marine Pollution Bulletin
Scientific reports, Jan 7, 2018
A correction to this article has been published and is linked from the HTML and PDF versions of t... more A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
Diverging semi-isolated lineages either meet in narrow clinal hybrid zones, or have a mosaic dist... more Diverging semi-isolated lineages either meet in narrow clinal hybrid zones, or have a mosaic distribution associated with environmental variation. Intrinsic reproductive isolation is often emphasized in the former and local adaptation in the latter, although both can contribute to isolation. Rarely these two patterns of spatial distribution are reported in the same study system, while this could provide fundamental information on the endless debate about the relative contribution of intrinsic reproductive isolation and local adaptation on the speciation process. Here we report that the low diversity long-snouted seahorse Hippocampus guttulatus is genetically subdivided into five cryptic semi-isolated lineages. Along the Atlantic coasts, northern and southern lineages meet and coexist with little hybridization in the southwest of France, forming a clinal hybrid zone. In the Mediterranean Sea, two lineages have a mosaic distribution associated with lagoon-like and marine habitats. A f...
Scientific Reports, 2016
Distribution shifts are a common adaptive response of marine ectotherms to climate change but the... more Distribution shifts are a common adaptive response of marine ectotherms to climate change but the pace of redistribution depends on species-specific traits that may promote or hamper expansion to northern habitats. Here we show that recently, the loggerhead turtle (Caretta caretta) has begun to nest steadily beyond the northern edge of the species' range in the Mediterranean basin. This range expansion is associated with a significant warming of spring and summer sea surface temperature (SST) that offers a wider thermal window suitable for nesting. However, we found that post-hatchlings departing from this location experience low winter SST that may affect their survival and thus hamper the stabilization of the site by self-recruitment. The inspection of the Intergovernmental Panel on Climate Change model projections and observational data on SST trends shows that, despite the annual warming for this century, winter SST show little or no trends. Therefore, thermal constraints during the early developmental phase may limit the chance of population growth at this location also in the near future, despite increasingly favourable conditions at the nesting sites. Quantifying and understanding the interplay between dispersal and environmental changes at all life stages is critical for predicting ectotherm range expansion with climate warming.
Frontiers in Marine Science
Loggerhead turtles are a globally vulnerable species of marine turtle. Broad-scale patterns of di... more Loggerhead turtles are a globally vulnerable species of marine turtle. Broad-scale patterns of distribution and abundance can provide regional managers a tool to effectively conserve and manage this species at basin and sub-basin scales. In this study, combined aerial and shipboard line transect survey data collected between 2003 and 2018 were used to estimate distribution and abundance throughout the Mediterranean Sea. Approximately 230,000 linear kilometers of survey effort, from seven different surveying organizations were incorporated into a generalized additive model to relate loggerhead density on survey segments to environmental conditions. Two spatial density models estimating loggerhead density, abundance, and distribution were generated – one a long-term annual average covering 2003-2018 and another covering the summer of 2018, when a basin-wide aerial survey, the Agreement on the Conservation of Cetaceans of the Black Sea, Mediterranean Sea and Contiguous Atlantic Area Su...
Animals, 2022
Chlamydiae are obligate intracellular bacteria that include pathogens of human and veterinary imp... more Chlamydiae are obligate intracellular bacteria that include pathogens of human and veterinary importance. Several reptiles were reported to host chlamydial agents, but pathogenicity in these animals still needs clarification. Given that only one report of chlamydiosis was described in sea turtles, and that chlamydiae might also be detected in hosts without clinical signs, the current study examined asymptomatic Mediterranean loggerhead sea turtles for the presence of chlamydial DNA. Twenty loggerhead sea turtles, rehabilitated at the Marine Turtle Research Centre (Portici, Italy), were examined collecting ocular-conjunctival, oropharyngeal and nasal swabs. Samples were processed through quantitative and conventional PCR analyses to identify Chlamydiales and Chlamydiaceae, with particular attention to C. pecorum, C. pneumoniae, C. psittaci, and C. trachomatis. Although it was not possible to determine the species of chlamydiae involved, the detection of chlamydial DNA from the collec...
Diversity and Distributions, 2022
Endangered Species Research, 2016
Marine Ecology Progress Series, 1999
Marine Ecology Progress Series, 2007
Marine Ecology Progress Series, 2000
Marine Ecology Progress Series, 2012
Marine Ecology Progress Series, 1999
Physiological and Biochemical Zoology, 2004
BMC Veterinary Research
Background: Caretta caretta is the most abundant sea turtle species in the Mediterranean, and stu... more Background: Caretta caretta is the most abundant sea turtle species in the Mediterranean, and studies on this species have vastly expanded during recent years, including those investigating gut bacterial and parasitic communities. Members of these communities have been reported with variable prevalence and pathogenicity, mainly depending on their host and environment (e.g. lifespan, distribution, habitat, diet, health status and stressors). Indeed, many species commonly inhabiting the sea turtle gastrointestinal tract exhibit an opportunistic behaviour. This study aimed to provide baseline data on enterobacterial and parasitic composition, through bacteriological culture-based methods and the FLOTAC parasitological technique, in cloacal and faecal samples of 30 live Caretta caretta, examined upon their arrival at the Marine Turtle Research Centre (Portici, Italy). Results: Enterobacteriaceae were isolated in 18/23 cloacal samples (78.3%), with Citrobacter and Morganella as the most common genera, followed by Proteus, Enterobacter, Providencia, and Hafnia. Parasitic elements were detected in 11/30 faecal samples (36.7%), with Enodiotrema, Rhytidodes, and Eimeria as most common genera, followed by Pachypsolus and Cymatocarpus. Additionally, Angiodyctium is reported for the first time in this host. The majority (47.8%) of sea turtles hosted exclusively Enterobacteriaceae, whereas 30.4% hosted both parasites and Enterobacteriaceae; the remaining 21.8% hosted neither of the agents. Conclusions: Bacteria and parasites evaluated in the present study are common in Mediterranean loggerhead sea turtles, with slight differences between the western and eastern basin. Although naturally present in the gastrointestinal system of free-living sea turtles, their relationship with these hosts might range from mutualism to parasitism. Indeed, members of the gut community might express their pathogenic potential in immune-compromised animals, such as those in rehabilitation facilities. Therefore, it is advisable to include in the standard work-up of rescued sea turtles a screening procedure for such opportunistic agents, in order to better evaluate the animal's health status and achieve timely intervention with appropriate treatment, thus improving rehabilitation. Furthermore, data collected from free-living sea turtles represent a starting point for investigating wild populations. However, further studies are needed to clarify the differences between sea turtle's normal gut microbiome and pathobiome.
Marine Pollution Bulletin
Scientific reports, Jan 7, 2018
A correction to this article has been published and is linked from the HTML and PDF versions of t... more A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
Diverging semi-isolated lineages either meet in narrow clinal hybrid zones, or have a mosaic dist... more Diverging semi-isolated lineages either meet in narrow clinal hybrid zones, or have a mosaic distribution associated with environmental variation. Intrinsic reproductive isolation is often emphasized in the former and local adaptation in the latter, although both can contribute to isolation. Rarely these two patterns of spatial distribution are reported in the same study system, while this could provide fundamental information on the endless debate about the relative contribution of intrinsic reproductive isolation and local adaptation on the speciation process. Here we report that the low diversity long-snouted seahorse Hippocampus guttulatus is genetically subdivided into five cryptic semi-isolated lineages. Along the Atlantic coasts, northern and southern lineages meet and coexist with little hybridization in the southwest of France, forming a clinal hybrid zone. In the Mediterranean Sea, two lineages have a mosaic distribution associated with lagoon-like and marine habitats. A f...
Scientific Reports, 2016
Distribution shifts are a common adaptive response of marine ectotherms to climate change but the... more Distribution shifts are a common adaptive response of marine ectotherms to climate change but the pace of redistribution depends on species-specific traits that may promote or hamper expansion to northern habitats. Here we show that recently, the loggerhead turtle (Caretta caretta) has begun to nest steadily beyond the northern edge of the species' range in the Mediterranean basin. This range expansion is associated with a significant warming of spring and summer sea surface temperature (SST) that offers a wider thermal window suitable for nesting. However, we found that post-hatchlings departing from this location experience low winter SST that may affect their survival and thus hamper the stabilization of the site by self-recruitment. The inspection of the Intergovernmental Panel on Climate Change model projections and observational data on SST trends shows that, despite the annual warming for this century, winter SST show little or no trends. Therefore, thermal constraints during the early developmental phase may limit the chance of population growth at this location also in the near future, despite increasingly favourable conditions at the nesting sites. Quantifying and understanding the interplay between dispersal and environmental changes at all life stages is critical for predicting ectotherm range expansion with climate warming.