Erica Nol Profile picture
7 Oct, 23 tweets, 18 min read
1/23 Thanks first to organizers of this new age conference, for inviting me to join in. I am very excited to be here with shorebird researchers from around the Twitter and real worlds #ISTC20 #SESH3 #ornithology #Waders
2/25 My tweets will explore the effects of extreme weather events on the demography of a small sub-arctic breeding shorebird: Semipalmated Plover (Charadrius semipalmatus) #ISTC20 #SESH3
3/23 Much attention of climate research and birds has been on warming: mismatching phenology in particular. But we know extreme weather can have a major impact on pop’n. Deaths of these songbirds probably due to recent fires and drought in western USA #ISTC20 #SESH3
4/23 Life histories of arctic-breeding birds have been moulded by extreme weather so why are we concerned? Big eggs, income breeders, body fat for cold spells #ISTC20 #SESH3
5/23 Meteorologists document consistent directional changes in frequency of unusual climatic events. Here are places in orange @CanadaNorthern that show more frequent freezing precipitation over last 50 y #ISTC20 #SESH3
6/23 My students and I have studied shorebirds nesting in habitats around Churchill, Manitoba, Canada for nearly 30 yrs. The longest running of these studies is on the Semipalmated Plover. #ISTC20 #SESH3
7/23 Fieldwork has been conducted regularly at 10 sites in region, based out of very comfortable @ChurchillNSC #ISTC20 #Sesh3
8/23 Habitats range from the edge of the boreal forest to pebble/sand beaches and mudflats to gravel exposed by removing tundra topsoil for several failed development projects. #ISTC20 #SESH3
9/23 Plover population has remained stable for nearly 20 y with some exceptions #ISTC20 #SESH3
10/23 First notable exception was result of 1992 Pinatubo volcanic eruption that cast a layer of dust across the globe that cooled the planet. Population declined to less than 20 pairs #ISTC20 #SESH3 Impacts felt on many bird species.
11/23 Second exception was in 2000. Very cold spring with ice and snow present well into usual breeding season #ISTC20 #SESH3
12/23 #ISTC20 #SESH3
13/23 Two key mechanisms link climate with bird demography: the impact on a bird’s physiology and the impact on their food. Slide shows typical Scholander curve for endotherms and for plovers, plotting ambient temp and bmr. @CondorJournal #ISTC20 #SESH3 Temp below 23o = elevated
14/23 Invertebrate prey are only active when threshold temp is reached. In this case 6o @kellielibera #ISTC20 #SESH3 Adults find food because they are more mobile. Chicks have harder time so effects can depend on life stage.
15/23 We have observed steady and significant decline of plovers since 2010 #ISTC20 #SESH3
16/23 Complete loss of plovers from three of most dependable and important sites #ISTC20 #SESH3 Note that many other researchers are noticing losses from study areas. #shorebirds
17/23 What has changed? Some supratidal nesting habitats degraded by staging geese and reduced to muddy soup. Ravens also seem more abundant.
18/23 Because we know temp has impact we want to see role in decline of persistent low temperatures caused by static polar vortices in spring. #ISTC20 #SESH3 Last five yrs have experienced low temps.
19/23 I used path analysis to look at independent effects of various potential causes of decline. Do combined effects of weather and steady decline in habitat quality explain local declines? #ISTC20 #SESH3 I used year as a proxy for a steady decline in habitat quality
20/23 Or perhaps a steady increase in predators, something that would impact only hatching or fledging success? #ISTC20 #SESH3
21/23 Analysis suggested weather and consistently cold springs impact future N through effects on timing of laying, which then affected fledging success. FS has little effect on future N. If late spring, birds give up on laying. Pop’n maintained by immigration #ISTC20 #SESH3
22/23 Impact of persistent polar vortex in other small Hudson Bay lowland breeding shorebirds very likely because their laying dates, hatching success and pop’n sizes correlated to those of Semipalmated Plovers #ISTC #SESH3
23/23 Thanks to all former Semipalmated Plover students and the funders and @IBIS_journal @WaderStudy #ISTC20 #SESH3

• • •

Missing some Tweet in this thread? You can try to force a refresh

Keep Current with Erica Nol

Erica Nol Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!


Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

Did Thread Reader help you today?

Support us! We are indie developers!

This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Too expensive? Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal Become our Patreon

Thank you for your support!

Follow Us on Twitter!