Microhabitats with distinct biotic and abiotic properties exist within landscapes, and this microhabitat variation can have dramatic impacts on the phenology and physiology of the organisms occupying them. The Antarctic midge Belgica antarctica inhabits diverse microhabitats along the Western Antarctic Peninsula that vary in macrophyte composition, hygric qualities, nutrient input, and thermal patterns. Here, we compare seasonal physiological changes in five populations of B. antarctica living in close proximity but in different microhabitats in the vicinity of Palmer Station, Antarctica. Thermal regimes among our sample locations differed in both mean temperature and thermal stability. Between the warmest and coldest sites, seasonal mean temperatures differed by 2.6˚C and degree day accumulations above freezing differed by a factor of 1.7. Larval metabolic and growth rates varied among the sites, and adult emergence occurred at different times. Distinct microhabitats also corresponded with differences in body composition, as lipid and carbohydrate content of larvae differed across sites. Further, seasonal changes in carbohydrate and protein content were dependent on site, indicating fine-scale variation in the biochemical composition of larvae as they prepare for winter. Together, these results demonstrate that variation in microhabitat properties influences the ontogeny, phenology, physiology, and biochemical makeup of midge populations living in close proximity. These results have implications for predicting responses of Antarctic ecosystems to environmental change.
|Number of pages
|Published - Oct 2021
Bibliographical noteFunding Information:
This project was supported by National Science Foundation Grants PLR-1341385 to REL, PLR-1231393 to DLD, and OPP-1850988 to NMT, and Hatch Project 1010996 from the USDA National Institute of Food and Agriculture to NMT.
© 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
- Physiological ecology
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics