Internship through the Cooperative Institute for Climate, Ocean, and Ecosystem Studies
NOAA Alaska Fisheries Science Center, Seattle WA, with Dr. Alison Deary
Larval Identification of Two Sand Lance Species (Ammodytes spp.) – 2018
Sand Lance (Ammodytes spp.) are an important genus of forage fish, as a food source for marine mammals, seabirds, and groundfish including cods. The Pacific sand lance (A. personatus) and the arctic sand lance (A. hexapterus) are two species that were recently separated via DNA analysis (Orr et al. 2015), but otherwise resemble each other closely, making field identification difficult in the Bering Sea, where their distributions overlap. I worked with larval sand lance specimens at the NOAA Alaska Fisheries Science Center to describe a developmental series for each species. These series were constructed by sorting through samples of each species collected in areas where their distribution did not overlap. Morphometric data were collected from the larval specimens in each species, which were analyzed using Linear Discriminant Analysis (LDA) and Principle Component Analysis (PCA) techniques. Both methods indicated that there were significant morphometric differences between the species larval stages as they developed, but these differences were too small to be detected by the naked eye. I also employed clearing and staining techniques to set up developmental series for bone development. This area is still being investigated. I noted differences in pigmentation between the two species that may prove useful in distinguishing between the two species’ larvae in the field. Results of the pigment differences must be validated by a DNA analysis of specimens collected from the overlapping range. Studies of these two closely related species can help us understand the difference in ecological role each species plays and how climate change will impact these species and their distributions in the future.
NOAA Alaska Fisheries Science Center, Seattle WA, with Dr. Alison Deary
Larval Identification of Two Sand Lance Species (Ammodytes spp.) – 2018
Sand Lance (Ammodytes spp.) are an important genus of forage fish, as a food source for marine mammals, seabirds, and groundfish including cods. The Pacific sand lance (A. personatus) and the arctic sand lance (A. hexapterus) are two species that were recently separated via DNA analysis (Orr et al. 2015), but otherwise resemble each other closely, making field identification difficult in the Bering Sea, where their distributions overlap. I worked with larval sand lance specimens at the NOAA Alaska Fisheries Science Center to describe a developmental series for each species. These series were constructed by sorting through samples of each species collected in areas where their distribution did not overlap. Morphometric data were collected from the larval specimens in each species, which were analyzed using Linear Discriminant Analysis (LDA) and Principle Component Analysis (PCA) techniques. Both methods indicated that there were significant morphometric differences between the species larval stages as they developed, but these differences were too small to be detected by the naked eye. I also employed clearing and staining techniques to set up developmental series for bone development. This area is still being investigated. I noted differences in pigmentation between the two species that may prove useful in distinguishing between the two species’ larvae in the field. Results of the pigment differences must be validated by a DNA analysis of specimens collected from the overlapping range. Studies of these two closely related species can help us understand the difference in ecological role each species plays and how climate change will impact these species and their distributions in the future.
Cleared and stained larval specimens; red indicates ossified bone, blue indicates cartilaginous structures
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Presenting at the Cooperative Institute for Climate, Ocean, and Ecosystem Studies poster session. View my poster here
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