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Tag: wildlife

Published in Marine Ornithology: Potential Northward Expansion of the Breeding Range of Red-legged Kittiwake Rissa brevirostris

by Bryce W. Robinson

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Black-legged Kittiwake (Rissa tridactyla; left) and Red-legged Kittiwake (Rissa brevirostris; right).

In a new paper published in Marine Ornithology, we report on an important result from the 2018 expedition to St. Matthew Island – documentation of previously unrecorded breeding activities for a Beringean endemic, the Red-legged Kittiwake (Rissa brevirostris). Our trip to St. Matthew was focused on Mckay’s Bunting (Plectrophenax hyperboreus) and Pribilof Rock Sandpiper (Calidris ptilocnemis ptilocnemis), where we both censused the populations of each and conducted a fine scale nesting study. While conducting this work, we opportunistically catalogued species presence and abundance, which led to the discovery of a large number of Red-legged Kittiwake occupying large cliffs on the northwest side of the island.

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Red-legged Kittiwake sitting on a nest (center) amidst Black-legged Kittiwake. This is one of ~50 individuals present at location B mentioned in the article.

Our paper in Marine Ornithology details what we found and where we found it, and also discusses the status of the species in the region. We discuss behaviors that we observed that indicated the birds likely attempted to breed on the island in 2018, although we were unable to confirm eggs or nestlings before we left in early July. Regardless, our observations of a few hundred Red-legged Kittiwake on St. Matthew is at least notable because it differs from past records that list only a handful of records of single individuals seen in waters near the island. Both the numbers and behaviors we observed indicate that the species has shifted its breeding range northward to include St. Matthew Island. Such a large latitudinal shift (~400 km) at a time of substantial change in the Bering Sea raises many questions, especially considering the status of populations at the core of the species breeding distribution, the Pribilof Islands.

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Figure 1. from the published report in Marine Ornithology 47(2). I was able to include a Red-legged Kitiwake illustration to elegantly communicate the distribution and relative size of Red-legged Kittiwake colonies, including the newly discovered colony on St. Matthew Island.

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Figures 2 and 3 from the report in Marine Ornithology 47(2). These figures describe the locations where birds were found, and their assortment on the cliffs relative to Black-legged Kittiwake.

As distributions of important food resources for seabirds shift, caused by aberrations in factors such as sea temperature, we expect to see distributions of seabirds that depend on these resources to shift as well (in the best case scenario). Currently, there seems to be ongoing massive starvation and die-off events of many seabirds in this region that are likely the result of an inability to respond to these changes in prey distributions. A northward shift in breeding distribution is promising for a Beringean Endemic, because it shows some plasticity in response to changes in resources. However,  we understand aspects of the Red-legged Kittiwake diet that partly explain why it holds a restricted range. Although a relatively small number of these birds have moved north to breed, characteristics of the habitat at and around St. Matthew Island may limit their success to produce enough offspring to maintain population stability. The story is ongoing.

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This shift in Red-legged Kittiwake distribution presents an opportunity to study species responses to climate change as they are occurring. Such study will not only further enlighten us on Red-legged Kittiwake life history strategies, but also on how species may or may not adapt to rapid fluctuations in food resources and climate caused by global anthropogenic activities. We need to stay focused on this region and these species, because they are telling us an important story.

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*Because of our observations in 2018, in summer 2019 (late July-August) USFWS returned to St. Matthew Island to conduct a comprehensive seabird survey of cliff nesting habitat and check for nesting Red-legged Kittiwake. They observed similar numbers at the same locations as our observations in 2018, and confirmed both eggs and nestlings. These observations confirm that the Red-legged Kittiwake now breeds on St. Matthew Island (at least in some years), and extends the breeding distribution for the species northward by nearly 400 km. 

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eBird checklists that document the 2018 Red-legged Kittiwake observations:

https://ebird.org/view/checklist/S47170141

https://ebird.org/view/checklist/S47199741

https://ebird.org/view/checklist/S47170187

https://ebird.org/view/checklist/S47170740

https://ebird.org/view/checklist/S47170322

https://ebird.org/view/checklist/S47170354

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Published in the Journal of Raptor Research: Dietary Plasticity in a Specialist Predator, the Gyrfalcon (Falco rusticolus): New Insights into Diet During Brood Rearing

by Bryce W. Robinson

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I’m privileged to once again see a painting of mine don the cover of the Raptor Research Foundation’s quarterly publication, the Journal of Raptor Research. This time, however, is more special since the painting of a Gyrfalcon carrying its prey, an Arctic ground squirrel, corresponds to the feature article authored by myself and Travis Booms, Marc Bechard, and David L. Anderson.

Our publication titled “Dietary Plasticity in a Specialist Predator, the Gyrfalcon (Falco rusticolus): New Insights into Diet During Brood Rearing” details patterns we documented through implementation of nest cameras in 20 Gyrfalcon nests in 2014 and 2015. The largest camera study of nesting Gyrfalcons provided us with many new insights into the biology of this species, some of which we have already published, some that we have not. In this publication, we document a previously undescribed shift in prey use throughout the nestling period, from a diet of mostly Ptarmigan early in the season, to squirrel in the late season. This shift to squirrel is an important consideration on many levels. It highlights the nuances to Gyrfalcon prey use in Alaska, and the potential importance of squirrels in the later season for juvenile success and development. The apparent importance of squirrels also has implications for understanding ecosystem changes and how shifts in prey landscapes may impact Gyrfalcon reproduction. The stage is set to explore further.

Below are a few photos that describe the work that went into producing this publication. These highlight a some of the >750,000 nest camera images we collected from which the diet was quantified, as well as photos of the field work, and the people that made this effort possible. 

You can read our paper in the Journal of Raptor Research here:

https://bioone.org/journals/journal-of-raptor-research/volume-53/issue-2/JRR-15-58/Dietary-Plasticity-in-a-Specialist-Predator-the-Gyrfalcon-Falco-rusticolus/10.3356/JRR-15-58.full

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A female Gyrfalcon feeds nestlings. Image copyright Bryce W. Robinson/The Peregrine Fund.

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A female Gyrfalcon feeds her newly hatched nestling, alongside hatching eggs. Image copyright Bryce W. Robinson/The Peregrine Fund.

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Female Gyrfalcon delivers an Arctic ground squirrel to nestlings. Image copyright Bryce W. Robinson/The Peregrine Fund.

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A female Gyrfalcon stands alongside c. 14 day old nestlings. Image copyright Bryce W. Robinson/ The Peregrine Fund.

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Parental care photo 1. A female (left) broods newly hatched young, reluctant to leave the nest at the male’s (right) arrival. Every Gyrfalcon would occasionally look at the camera, as seen here, but were otherwise unaffected by its presence. Image copyright Bryce W. Robinson/The Peregrine Fund.

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Parental care photo 2. In some cases, males were keen to participate in brooding and feeding young, as is shown here. In even fewer cases, the females were tolerant of this behavior. Image copyright Bryce W. Robinson/The Peregrine Fund.

Bryce and Gyrfalcon nest camera

Bryce W. Robinson sights in a nest camera at a Gyrfalcon nest. Image by Caitlin M. Davis.

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Bryce W. Robinson rappelling into a Gyrfalcon nest in western Alaska. Image by Neil Paprocki.

Special thanks to the following people that made the field work happen

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John Earthman and Tinsel

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Neil Paprocki

Ellen in Gyrfalcon nest with nestling

Ellen Whittle holding a Gyrfalcon nestling in 2015.

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Mark Jeter and Ellen Whittle against an Alaskan landscape in 2015.

Special thanks to the institutions that made this work possible: Boise State University, Alaska Department of Fish and Game, and The Peregrine Fund

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Bearded Vulture Illustration for HawkWatch International Shirt Design – Support Worldwide Vulture Conservation

by Bryce W. Robinson

Bearded Vulture

I was given the opportunity to provide a t-shirt design for HawkWatch International featuring the Bearded Vulture. The design and shirt are meant to both raise awareness and support for the important conservation science work of HWI focused on Old World vultures. Old World vultures are facing a myriad of threats that are impacting populations, to the point that most face extinction. Please, learn more about the work of HawkWatch International and consider helping in any way you can. Visit their website to read about the vulture work, and more.  

Click on the photo below to purchase a shirt, and support vulture conservation.

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Remembering Tom Cade: 1928-2019

by Bryce W. Robinson

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Showing Tom Cade an occupied Gyrfalcon nest with a nest camera, recording images for The Peregrine Fund’s Gyrfalcon Conservation Program.

Today I’m remembering Tom Cade, ornithologist and conservation giant. Tom passed away yesterday at the age of 91. His legacy is widespread, not only across the earth but through time, for generations into the future. Rather than describe this enduring legacy, I want to here describe one of my most cherished memories of spending time in the field with Tom as I showed him my study area during my Gyrfalcon work.

While I was conducting my field study on nesting Gyrfalcons in western Alaska, Tom came to visit for a few weeks. He stayed with me and Ellen Whittle, my field partner, in a small apartment in Nome. It’s hard to describe the conditions in such an apartment, but the few photos I’ve included here should be telling. I was so impressed with Tom, since he seemed entirely content to be in this run down shack of an apartment, cramped with two young ambitious biologists. In fact, I think he enjoyed it!

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Tom Cade and Travis Booms, walking along a tundra road on the Seward Peninsula.

Of course, we only spent time indoors when the rain wouldn’t allow otherwise. We made many trips out into the tundra to show Tom around, and Tom also spent time with Travis Booms and Joe Eisaguirre as they flew around the peninsula in a helicopter, accessing Gyrfalcon nesting sites. As we drove the roads with Tom, looking for wildlife and checking on raptor nests, we listened intently as Tom told stories of his last visit to the region nearly 60 years prior. He told us stories of a mid-tundra train wreck, seeing his first Gyrfalcon, and how the Nome area truly was different from his last visit, with more vegetation than he had previously recalled.

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Tom Cade, a man with an incredible legacy and an excellent sense of humor.

Apart from his unending wisdom and knowledge, I was impressed with Tom’s sense of humor. He was having fun, and wasn’t afraid to let it show. As is appropriate in western Alaska, July is a time for King Crab. With Tom in town, we had a great excuse to occupy our time during bouts of rainy weather with Crab feasts! I’ll never forget having crab with such excellent people, and I could tell from the photo above that Tom was having a great time as well.

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Crab Feast! Tom Cade, Bryce Robinson, Ellen Whittle, and Joe Eisaguirre. I think Joe was hitting his limit at this point. Photo courtesy of Travis Booms.

After Tom departed Nome and returned to his home in Boise, and I came home following the field season, we saw each other only intermittently. The last time I saw Tom Cade was in a meeting, only a few months ago. He listened, and only spoke when he needed to. But, he was participating. His passion was enduring, so much so that even until the last parts of his extraordinary life, he participated in the work he had set forth.

It is sad to see people go, but it provides us all a perspective on our lives, how we choose to live them, and who we are and want to be. Reflecting on Tom’s life has caused me to reflect on myself, and how I might honor and continue what the man did for multiple species facing extinction, and for the people he inspired, inspires and will inspire. I’ll take that spirit into the future, and do with it what I can.

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Generations of Gyrfalcon researchers: Bryce Robinson, David L. Anderson, Tom Cade, Travis Booms, and Mike Henderson.

If you’re unfamiliar with the legacy of Tom Cade, visit The Peregrine Fund’s website. Everything you see there is a testament to Tom’s legacy, and what he created. Also visit the following link for a great video highlighting Tom’s life: https://www.peregrinefund.org/people/cade-tom