Upcoming Event: April 14, 2022- Denver Holt presents for ARCUS Arctic Research Seminar
Mark your calendars: later this week Denver is giving an online seminar for the Arctic Research Consortium of the United States (ARCUS). He will be sharing insights and information from his decades-long on-going research on Snowy Owls and lemmings in the Arctic.
The seminar will be online, and is free and open to the public. Registration is required.
When: Thursday, 14 April 2022 - 9:00am to 10:00am (AK)
Where: Online.
Register here: Denver Holt: Highlights of 30 Years Studying Snow Owls and Brown and Collared Lemmings at Utqiagvik, Alaska- 14 April 2022
From the seminar description:
"For 30 years (1992-2021) Denver and colleagues have been studying the breeding ecology of Snowy Owls at Utqiaġvik, Alaska. It is the longest continuous breeding study in the word, and conducted by the same researcher. They have studied 284 nests and banded ~800 owls, mostly nestlings.
Researchers have recorded >43,600 prey from pellets, and >3,300 prey cached at nests, of which >2,500 have been lemmings. For lemming carcass cached at nests, they recorded sex, body mass, relative age, and reproductive status.
Researchers have also monitored lemming population fluctuations through snap-trap methods. Over 30 years, more than 3,600 lemmings have been snap-trapped. They have recorded; sex, body mass, relative age, reproductive status, embryo counts, parasites, infectious diseases, and so forth. Although population fluctuations do exist, predictable cycles in the strictest definition of the word do not.
Additionally, researchers attached the first satellite transmitters to Snowy Owl in the world, recorded nest site characteristics, established genetic markers for estimating population, conducted hormone research in relation to pre-fledging nest departure of young, conducted growth rates and plumage development studies, and behavioral studies. Additionally, they have conducted an entire review their world ecology and population estimates.
Snowy Owl nesting numbers at Utqiaġvik have been declining since about 2009. Reasons are not known but climate change is suspected.
However, alternative questions for this decline do exist. For example, did the ~10 years of killing Arctic foxes to protect the threatened Steller’s Eider disrupt the entire ecosystem around Utqiaġvik? Do Brown and Collared lemmings and Arctic Fox have a relationship that benefits all three species? Did the removal of Arctic fox increase White-fronted, Brandt, and Snow goose numbers? And, in turn does the grazing impact on tundra plants, compete with lemmings, and reduce forage quality, quantity and ground cover, important for lemming survival?
These questions will be addressed in future analysis."