Shell lengths of pteropod, Limacina helicina antarctica, collected from the PAL LTER sediment trap along the Western Antarctic Peninsula, 2004 - 2018, and from net tows 2017-2018.

• Main Authors: LTER, Palmer Station Antarctica, Thibodeau, Patricia
• Format: Dataset
• Language: English
• Published: Environmental Data Initiative 2020
• Subjects: Antarctic; Antarctic Peninsula; Anvers; Anvers Island; Palmer Station; Palmer-Station; Antarc*; Antarctica; Limacina helicina
• Online Access: https://dx.doi.org/10.6073/pasta/237226c00e89aa0435d825d7015b3a8f; https://portal.edirepository.org/nis/mapbrowse?packageid=knb-lter-pal.307.4

Pteropod, Limacina helicina antarctica, is an abundant zooplankton along the Western Antarctic Peninsula (WAP) and prey for higher trophic organisms. Changes in the pteropod (pelagic snail) phenology (life history) have important implications for regional food web dynamics. Pteropod shell lengths were collected from the PAL LTER sediment trap located along the northern continental shelf of the PAL LTER sampling grid, 2004-2018. PAL LTER has deployed a time-series trap near 64.5° S, 66.0° W since late 1992. The trap is moored in 300 m depth and collects sinking particles at 170 m. Pteropod samples are stored in 21 sample collection bottles on the sediment trap that were prepared with a Milli-Q deionized water rinse and filled with 7.5 g NaCl l-1 solution and 2% borate-buffered formalin in filtered seawater (34 ppt), with a final salinity concentration of 41 ppt. L. h. antarctica shell lengths also collected during the PAL LTER 2018 January offshore cruise and for four months at Palmer Station, Anvers Island (November 2017 to February 2018). L. h. antarctica and all other macrozooplankton collection on the PAL LTER cruise are performed with a 2 m square frame Metro net (700 µm mesh), towed obliquely to a depth of 120 m. At Palmer Station, pteropods are collected with a 1 m x 1 m square frame Metro net (700 µm mesh) and a 1 m diameter ring net (200 or 500 µm mesh), towed obliquely to a depth of ~50 m. Shell lengths are determined by measuring from the opening of the shell aperture directly across the diameter of the shell. The shell lengths analyzed within the WAP region are used to determine phenology patterns in pteropod population dynamics and changes thereof over time.