A Big Year? The View from the Arctic

JF TherrienUpdates8 Comments

The tents of the Laval University team are all but lost in the immensity of Bylot Island in the Canadian Arctic. (©Jean-François Therrien)

The tents of the Laval University team are all but lost in the immensity of Bylot Island in the Canadian Arctic. (©Jean-François Therrien)

Again this summer, I was part of a crew heading up North to one of the primary snowy owl breeding grounds in the Eastern Canadian Arctic. There, from mid-May to late-August, a team of 25 to 40 people from all spheres of research (plant, mammal and bird biologists, field assistants as well as local Inuit) devoted themselves to studying every inch of the magnificent tundra landscape.

Each year we have the same question: Will it be a “snowy owl year”? Indeed, our long-term ecological monitoring on Bylot Island in Nunavut, Canada, has made it pretty clear — lemming populations fluctuate tremendously from year to year and so do the owls that feed heavily on them.

When lemmings reach peak abundance (which happens roughly every four years) — and only during those years — snowy owls invade the site and nest in big numbers. Because summer 2014 was a banner year for both lemmings and owls on Bylot, odds were low for summer 2015 being a good nesting season (Only once over the last 27 years of monitoring did snowy owls nest on our study area two years in a row.)

And the predictions held true. There were some lemmings this summer, but the numbers were not high. Thus it was no surprise that we found no breeding owls on the 500 km2 study area that we survey every year.

Nevertheless, it was a very nice and productive summer. The research and monitoring go on, even if no owls show up to breed. From a scientific point of view, counts of zero are worth as much as any banner year (although they are of course less fun).

There were also plenty of other projects going on this summer on Bylot Island. Monitoring of cliff-nesting raptors such as peregrine falcons, gyrfalcons and rough-legged hawks always brings a thrill. Moreover, we succeeded in deploying the first GPS/GSM transmitters on rough-legged hawks on their breeding grounds in North America.

Three snowy owl chicks huddle at their nest on Bylot Island, where SNOWstorm team member Jean-François Therrien works every summer. (©Cassandra Cameron)

Three snowy owl chicks huddle at their nest on Bylot Island, where SNOWstorm team member Jean-François Therrien and his colleagues work every summer. (©Cassandra Cameron)

As for the snowy owls, chances are that they nested somewhere else in the vast Arctic tundra where lemmings were more numerous this summer. Indeed, the owls that we have tracked since 2013 and 2014 as part of Université Laval’s satellite telemetry project settled and likely bred on Baffin and South Hampton Islands in northern Canada. We have no confirmation on the success rate of those nesting attempts, however, or on the lemming situation at those sites during summer. Moreover, Russian and Norwegian colleagues have reported fair numbers of breeding pairs on their side of the globe. (The Yamal Peninsula in Siberia apparently had particularly high numbers of breeding owls.)

In North America, the only two other sites that I am aware of reporting breeding owls in this summer were Barrow, Alaska (where long-time researcher Denver Holt found three nests) and Bathurst Island in Canada (for which I didn’t have any precision on the number of pairs, but their presence was confirmed). That doesn’t mean that there were no other sites with breeding snowy owls in North America. But since most snowy owls creating a major winter irruption are young birds dispersing south for the first time — and given the low density of nests so far reported from the North American Arctic — I would predict a slower winter, at least in the eastern North American states.

However, snowy owls have a tendency to surprise us and to do exactly what we didn’t expect, so we’ll have to wait and see what might come to our latitudes this winter. Indeed, some early reports of snowy owls (as of 15 Nov.) have already been heard from Wisconsin, Michigan, Minnesota and Saskatchewan, to name only a few places. However, this broad region is known to be used regularly by wintering snowy owls, so this might only be “regular” movements. The same may be true of the handful of reports from the Northeast as far south as Pennsylvania. In any case, we’ll keep you updated as the winter of 2015-2016 unfolds.

(SNOWstorm team member Dr. Jean-François Therrien is a senior research biologist at Hawk Mountain Sanctuary in Pennsylvania, and has been studying snowy owls in the Arctic for years with Laval University in Quebec.)

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  • Elaine

    Thank you for your informative updates. Look forward to seeing some Snowy’s this year in Northeast!

  • Jerry Maynard

    Thanks for the update.  We run a raptor rehab and education center in the UP of MI.  We got many reports of snowies showing up here in the UP between Oct. 19-28.  We rescued 6 that were too weak to fly; two survived and are doing well and will be released back to the wild this Sunday, 11/22.  The other 4 died soon after admission to our center.  All were extremely emaciated, dehydrated and exhausted.  We sent pics to Alec Lindsay who identified them all as hatch year males.  I have not heard any reports of snowy spottings east of Lake Huron or west of MN, so appears to be a very focussed irruption, if it can be called that.  Carcasses of the dead birds were sent to MDNR wildlife path lab in Lansing MI, which confirmed cause of death as dehydration and starvation.  Most of the birds we got in had mites, and one had a bad infestation of flat flies.  Other than that, we did not find anything wrong other than the emaciation.  Amazing birds.

  • Thanks for the update on your end, Jerry — we know you’ve been busy. We want to thank you and the other rehabbers in the region who have been working with state agencies and SNOWstorm to have DOA snowies and those that didn’t make it necropsied and tested for toxins, pathogens, etc.

    As you say, this appears to be a very focused movement of snowies into the western Great Lakes and Plains — thin birds have been reported from Saskatchewan and the Northwest Territories. Dave Evans at Duluth, who has been studying snowies for years, and Tom Erdman at the Ritcher Museum in WI, have both noted that very early flights like we saw last month are usually thin birds. Unlike the big irruptions we’ve seen in recent years, which seem to be generated by abundant breeding seasons producing a lot of fat, young birds, this appears to be the kind of “classic” irruption seen among great grays and hawk owls, driven by hunger.

    Interestingly, Norman Smith in Massachusetts has moved a number of snowies from Logan Airport in recent weeks, and says that all thus far have been fat, healthy juveniles. As JF points out in this blog post, we don’t really know what’s going on in most of the Arctic – some areas may have lemming booms, others may have prey crashes. We’re undoubtedly seeing snowies from different areas, and coming from starkly different circumstances, this winter.

  • Jerry Maynard

    Thanks, Scott.  We have learned so much about these beautiful birds this year, and Project SNOWstorm has been fascinating.  Keep up the good work.

  • Pam Novak

    Our first Snowy Owl was admitted already for rehab after being hit by a vehicle on or just before the morning of November 19th in Dieppe, NB. For a week or so before, the Owl was seen in the marsh around the city, flying but being harassed by the local crows. There have been various reports of Snowies in the province of NB in November. https://www.facebook.com/media/set/?set=a.1042723409091430.1073741862.207543799276066&type=3

    Cheers, 
    Pam Novak
    Atlantic Wildlife Institute

  • Ryan Brady

    Things have been anything but regular in Wisconsin, where roughly 82 Snowies have been tallied already this season, including 65 from the Oct 15-31 period alone. The proportion of birds in poor body condition is much higher this year than in most, including the past two big irruption years. Interestingly, observations of new owls as well as those that had initially arrived in October have plummeted in November and thus it remains to be seen what this winter may have in store. Regardless, we’ve already far exceeded what an average year would bring to the Badger State.

  • Greg Arnold

    Owls are cool birds

  • Patricia

    Thanks for the interesting updates. Looking forward to a seeing our first snowy owl of the season!! There’s been a couple sightings in the Ottawa area but seemed like passer-byes.