In 2014 we set out to determine whether bear saliva, collected by swabbing the partially-eaten remains of salmon carcasses, could be used to identify individual bears, a method intended to add another tool to the toolbox of wildlife researchers and managers. Being able to identify individual bears from their saliva (which is collected noninvasively– no need to trap the bear!) is a boon to bear biologists. This type of genetic information can provide insight into population densities, movement, and feeding behavior. The results from our work were published today in the journal PLoS One. All Public Library of Science journals are open access, so no fees are required to read or download the paper. You can check out our newest publication here.
We’ve recently published a paper detailing some of the results from our fieldwork and research in Southeast Alaska. This latest article discusses how habituation to human activity in some bears and fear of human activity in other bears differentially effects bear activity patterns in and around Chilkoot Lake State Park. The article is open-access, which means you do not need any special subscription or password to access the article and read it. You can read the article here, for free.
It can take a long time from data collection to publication. (more…)
For any Santa Cruz or Bay area residents out there, Rachel will be giving her dissertation defense talk next Monday, May 16th from 12:30 to 1:40 PM on the UCSC campus. She’ll be going over the results her research, conducted over the previous five years in and around Haines, Alaska, much of which was detailed here on the blog. She’ll discuss information on subsistence fisher’s needs and harvest practices, bear feeding behavior in relation to human activity, and eagle movement strategies throughout the north Pacific. Any of you that have been keeping up with the Ecology Alaska website and blog that a) are in the neighborhood and b) are interested in seeing how the fieldwork and progress detailed on the website translate into results and scientific output should consider coming by! The event is free and open to the public.
What: Dissertation defense talk, “End of the line: terrestrial salmon consumers and ecosystem-based fisheries management in the north Pacific”
When: Monday, May 16th, 2016, from 12:30 to 1:40 PM
Where: Room 221, Interdisciplinary Sciences Building, UCSC campus. If you need directions to the building, please click here.
Happy Spring! Here’s an update on what our GPS-tagged eagles have been up to since this winter.
Káa (3C): Káa didn’t move too much this winter. Unlike previous winters, when he traveled southward toward Prince Rupert, Káa mostly stuck around the Copper River and other watersheds in the area. Recently he’s spent time around Yakutat Bay, and he’s currently hanging out in Juneau.
Shaatk’ (4P): Just as in December, Shaatk’ has stayed very close to Admiralty Island. Most recently she’s been hanging out around Pybus Bay, in the southeastern corner of the island.
Shaa (2Z): Shaa seems to have his annual travel pattern down pat. He spent the winter in Prince Rupert near the landfill, then returned to his summer grounds in early spring. He’s currently hanging out near Whitehorse, YT.
Xeitl (4R): We were concerned that we wouldn’t hear from Xeitl again after losing contact with her transmitter this winter. She popped back up again in spring though, when her transmitter finally recharged. Although we don’t know her whereabouts this winter, she’s currently hanging out around Juneau. Welcome back, Xeitl!
Kút (3R): Kút is currently firmly on her nesting territory at the tip of Admiralty Island. I wonder if she hatched chicks this year?
Ixkée (2T): Ixkée visited Berners Bay this spring, likely attracted to spawning eulachon (also known as hooligan or candle fish). Recently she’s been spending most of her time on the Taku River.
Tláakw (3G): Juneau is a pretty popular spot right now! Tláakw is hanging out there, too.
Keen (3Z): Keen also visited Berners Bay for hooligan, but most recently he’s been hanging out across Lynn Canal from Berners, around St. James Bay.
Kínaa (4Y): We lost contact with Kínaa midsummer last year. After not having received a single location from him for more than six months, we were convinced his transmitter had completley failed. But somehow, it didn’t! It managed to recharge and we’re able to keep up with Kínaa again, at least for the time being. In the past few weeks, he’s been spending time in Glacier Bay and around Dundas Bay, to the southwest of Glacier Bay.
Happy holidays! Here is the fall/winter eagle update. For more detailed information on where each individual eagle has traveled since springtime, you can view their webpages (linked below) or check out Eagle Tracker. This year we’ve definitively lost four transmitters, and possibly a fifth as well. This is an unfortunate outcome, as we’d certainly hoped to be able to track these birds over longer time frames. Apart from Ch’áak (3M), who was suspiciously absent from his nest site this year, there were no strong indications from relocations that any of the eagles died, but it is always a possibility. So, too, is transmitter failure– these transmitters are not infallible, and the batteries often do not work as planned. It’s also possible the eagles tired of the harnesses and picked them off. With a bill as sharp as a raptor’s, it’s not difficult for eagles to get through the Teflon ribbon if they want the harnesses off! Nonetheless, we’re fortunate enough to still be actively tracking seven individuals, with an eighth that might pop back up if the battery on her transmitter recharges. Here’s what we know: (more…)
Recently I had the opportunity to assist the Alaska Department of Fish and Game (ADFG) with some moose-based fieldwork in Gustavus, Alaska. It’s been strange for me to spend the summer and autumn in Oregon instead of Haines, so I jumped at the chance to get back up to The Last Frontier. Research in Gustavus is headed by ADFG wildlife biologist Kevin White. Kevin has been studying moose and mountain goats throughout northern Southeast Alaska for years, and his research projects have provided a lot of valuable information on moose and mountain goat behavior, reproductive success, and causes of mortality. While Kevin was away at a research conference, I joined his technician and friend of Ecology Alaska, Yasaman Shakeri, in the field. (more…)
Some of you may have noticed that the site has been down for the past couple weeks. We’ve had issues with our host unexpectedly dropping us, so we had to find a different host and migrate the site over from backups. Unfortunately, this migration process was not seamless and we’ve lost some content along the way. In the coming weeks, I will try to fix issues with lost content, missing photos, and ‘fatal errors’ that might show up as you browse the site. Errors and missing content seem to be associated primarily with the home page, and the “About” and “People” sections of the site. Please bear with me as I try to sort everything out. In the interim, Eagle Tracker seems to be functioning more or less normally and I will continue with monthly blog posts. If you come across any issues while browsing, please let me know using the “Contact Us” page and I’ll try to address them
Thanks for your patience!
We recently published a paper covering some of our findings from the first few years of the Ecology Alaska project. Our article was released in the open-access journal PeerJ. The paper describes what we found from the camera trapping that Taal and Jenn did in 2011, and that Rachel did in 2012 and 2013.
What is an open-access journal? Just like it sounds, it’s a journal that is free and open for anyone to access. Most scientific journals are fee-based, meaning scientists either have to subscribe to a journal to access issues and articles, or be a part of an institution, such as a university, that pays the subscription fees. The open-access model works differently. No subscription or access fees are required, meaning any individual can read what’s published. That includes you!
You can check out our new paper here.
Say you’re an ecologist, and you want to know how many individuals of a given species there are in an area. There are several ways to census the population to make an estimate. You could, for example, set out traps to capture individuals and mark them somehow, with ear tags or microchips or some other means of identification. After a period of time after which you’re not trapping any additional new individuals, you would use a statistical model to determine how many individuals there likely are total, given how easy the species is to catch, how many you caught, and whether you had any recaptures. Pretty straightforward, right? (more…)
We’re well into summer now and things are heating up. A very dry winter and a strong heatwave this spring has made things tough across the state– Alaska is now experiencing record numbers of wildfires. The southeast doesn’t seem to be as bad off as the interior, which is lucky for our eagles! Here is the summertime eagle update! For more detailed information on where each individual eagle has traveled since springtime, you can view their webpages (linked below) or check out Eagle Tracker.
Shaawát (3E): Shaawát has been a tricky one lately. Although her movements have been perfectly normal, the information we’ve received from her transmitter has been spotty at best. We believe her transmitter could be failing, in which case we might no longer receive tracking information from her. Her last transmission, which came in early May, showed her up on the Chilkat River.
Káa (3C): Káa has been bouncing around quite a bit. When he left Prince William Sound and headed southward in springtime, he spent some time on the Chilkat, returned north for a bit, headed south again to the Stikine River, then north again. He returned to his summering area on the Copper River for a while but most recently started heading southward again back toward the Chilkat.
Shaatk’ (4P): Shaatk’ seems to be spending increasingly more time around the southern half of Admiralty Island, occasionally in and around Angoon but otherwise making circuits of the coastline.
Shaa (2Z): Shaa didn’t spend much time in Price Rupert this spring before returning northward to Whitehorse. He didn’t make too much of a crazy springtime journey this year, but he did make it up to Carmacks, YT at one point. He’s been floating among Whitehorse, Haines Junction, and the Chilkat Pass.
Xeitl (4R): Xeitl didn’t spend much time in the south either. She returned to the general Juneau/Douglas area, where she’s been hanging out, and occasionally visiting Berners Bay.
Kooshtéeni (4C): Kooshtéeni headed north late spring up toward Yakutat, before returning to the land around Juneau. Most recently she’s been heading up the Taku Inlet, south of Juneau.
Kút (3R): Kút appears to be making another breeding attempt this season, sticking hard and fast to her nesting area/territory at the tip of Admiralty Island.
Ixkée (2T): Ixkée made a quick visit down south to Prince Rupert in late spring before returning to the Chilkat, where she’s spent most of her time since.
Tláakw (3G): Tláakw didn’t spend much time on Vancouver Island– a few weeks at most– and then he returned north. Lately he’s been hanging out around the northern end of Chicagof Island.
Keen (3Z): Keen made a brief foray to the Nass River on his northward journey from Vancouver Island, and then continued on to Berners Bay. He’s made a handful of north-to-south loops, once going as far south as the Stikine River, but primarily between Berners and the southern part of Admiralty.
Kínaa (4Y): Kínaa spent some time near Yakutat late spring, but more recently has been circling among Glacier Bay, Admiralty Island, and Chicagof Island.
Ch’áak (3M): Like Shaawát, Ch’áak’s transmitter has been providing information inconsistently, and is possibly failing. We haven’t heard from him from March, and his nest on Douglas Island is empty this year. It is possible he has died.
Long time no see, eh? I’ve been busy since the last update, leaving Alaska mid-March and traveling down to Corvallis, OR and Oregon State University to work in the fledgling lab of Dr. Taal Levi with the bear scat and saliva samples collected last summer. Rigby and I have been here for nearly three months now!
Working with DNA is not easy, or cheap, or quick. Each step in the process requires some experimentation to determine what works best; how to sample the scats, for example– which are to wet or too degraded to even try, or what to do if they’ve dried out. Then, how best to extract the DNA from the samples? And afterward, what’s the best way to genotype individuals?
It’s been a strange winter here in Alaska, with unseasonably warm weather and very little snowfall statewide. Southeast Alaska has had an extended autumn of sorts, filled with plenty of rainfall and relatively mild weather. This seems to be reflected in the eagles’ behavior; although a couple traveled southward to overwintering areas, many stayed put in and around the Chilkat Valley. It remains to be seen if spring will bring more ‘normal’ weather for the region, but for now, here’s an update to Eagle Tracker to catch up with the winter movements of all the birds. We temporarily lost contact with five transmitters this winter (batteries won’t properly charge when days are short and nearly always overcast) but they’ve all come back online in the past few weeks. Check out the eagles’ movement pathways by visiting their individual pages:
Shaawát (3E): Shaawát spent her winter hanging out on the Chilkat River. We expect she’ll be checking Berners Bay for hooligan soon.
Káa (3C): Káa spent much of his winter up in the interior of Alaska, east of Prince William Sound. He’s been very slowly making his way south, and is now back on the coast, near Yakutat.
Shaatk’ (4P): Shaatk’ also spent much of her winter on the Chilkat River, up near Klukwan. She recently moved southward to the Nass River, in British Columbia.
Shaa (2Z): Shaa spent most of his winter in Canada, near the Chilkat Pass. He only recently returned to his typical winter home in Prince Rupert, BC.
Xeitl (4R): Xeitl also spent most of her winter on the Chilkat. She did eventually travel south, and is currently hanging out around Terrace, BC.
Kooshtéeni (4C): Kooshtéeni, like a lot of the others, also spent most of her winter on the Chilkat River. She’s recently been hanging out around Chichagof Island.
Kút (3R): Kút has spent the winter sticking around her territory at the tip of Admiralty Island. With the nesting season fast approaching, it doesn’t look like she’ll be headed anywhere else anytime soon.
Ixkée (2T): Ixkée also spent her winter on the Chilkat River (are you sensing a theme here?). Seems like she’s recently been checking up on Berners Bay.
Tláakw (3G): It’s not just the females spending the winter on the Chilkat. Tláakw spent most of his winter in the area, too. Last year, he made it down to Vancouver Island at the end of December and spent his winter there. This year, we thought he wouldn’t go south at all… until earlier this week, when he did.
Keen (3Z): Keen was one of the only eagles to make a true southward bid this winter. He left the Chilkat in December and made it to Vancouver Island (just 90 miles above the Canada/Washington border) in early January, where he spent the remainder of the winter. Interesting, seeing as how he didn’t spend any of the winter at all last year any farther south than Prince Rupert. Most recently it seems he’s heading north again, gradually making his way up the coast.
Kínaa (4Y): Kínaa also made it back to the Chilkat, and likely spent much of his winter there. He’s now heading up the coast, toward Yakutat.
Ch’áak (3M): Ch’áak is sticking fast to his territory near Juneau. He has a nest near the small boat harbor in Douglas. I’ve spotted him numerous times this winter near Sandy Beach. If you’re ever in the area, keep an eye out for him!
Greetings, everyone. It’s been a while– winter is slow and with no fieldwork ongoing, there are few updates to share. Next month we’ll be starting in on the lab work to process the bear DNA from samples collected this summer. In the interim, I’m slowly working on updating Eagle Tracker and have begun the first steps for data analysis of our camera trapping photos, eagle movement patterns, and the subsistence fishing survey.
Photographer John Dengler, who joined us in the field to document our first eagle capture season, joined me again in the field last autumn while I was collecting bear saliva samples from chum salmon carcasses. He has posted a series of photos and a blog entry about his time in the field. Check them out!
As is typical, now that winter has set in blog posts will be few and far between for a while. I’ll aim for once monthly. Rigby and I have moved slightly south to Juneau for the winter. I’m trying to take advantage of the limited daylight and access to personnel with Alaska Fish and Game and the US Fish and Wildlife Service to get a head start on data analysis for the eagle data. In early spring we’ll head south to Oregon to a genetics lab to begin extracting DNA from the bear scat and saliva samples we collected this summer.
Except in a few rare circumstances, black and brown bears are now all denned up to hibernate for the winter. The eagles seem to be taking advantage of a very mild start to winter here in Southeast Alaska and haven’t moved much at all. Whereas in the past two years we’ve seen most male and immature eagles leave the northern part of their ranges to head south for the winter by this point, this year, with relatively mild temperatures and rain instead of snow across much Southeast Alaska, the eagles seem to be staying put. Coho continue to run up the Chilkat River late into December and into early January, and it seems that a combination of above-freezing temperatures and available fish mean that the eagles will stick around. With not much ice on the river competition isn’t much of a big deal– there are many places to access fish and so the eagles can spread out and take their fill. (more…)
One of the best things about the GPS tracking devices we use on our bald eagles is the fact that they’re solar powered, so they last a lot longer than transmitters with conventional batteries. Batteries are heavy, and birds can only comfortably carry so much weight, so the life of a transmitter is often restricted by the size and weight an individual bird can carry. Historically, batteries on VHF radio transmitters for bald eagles lasted typically only nine months. Short lifespans means limited information about the ways birds move interannually (between one year and the next). Do birds visit the same places year after year? Do they follow the same pathways when they’re flying? Or do they explore more, visit different areas, and travel widely? (more…)