Breeding season is often a hard time for the tender hearted among us. The joy of watching an animal construct a nest just to see their efforts cut short by predation is painful. Likewise, finding a dead chick is tough, and prompts many to ask how they could have prevented such loss and better protected them.
I appreciate the people that bring me these questions so much. That care so deeply they would put in the effort to seek out these answers from a scientist and spend their time doing what I suggest. These are good people.
But whether you’re asking how to protect birds from crows, or crows from other animals, my answer is always the same. As hard as it is to watch animals get eaten, it’s vital to remember that predation is what keeps wildlife wild. It’s what keeps ecosystems complex & beautiful.
When we get into the business of deciding that (native, natural) predators are bad, and attempt to take action against them, we are denying the very wildlife we want to thrive from facets of their identity that make them who they are. Prey communities are shaped by the predators that have historically hunted them, and vice versa. Whether it’s how cryptic the chick’s color pattern is, how many eggs the female lays, where they build their nests…not one corner goes untouched. It’s this very process that has made something so beautiful that we can’t stand to see it harmed. But for communities to function that death is essential.
Predation is the transfer of life and that life is a gift. It’s a gift that ensures the survival of another, and even if we don’t know that individual as well as the one we watched perish, it’s not for us to assert that it, or its offspring, deserves that gift any less.
On the other hand, finding a dead, otherwise unharmed, chick can feel less…purposeful. “Why was it out of the nest so early?” “I read to leave it alone and it died anyway…should I have stepped in?” “I feel so bad I couldn’t save it!”…These are common responses.
But while it’s true that baby birds do sometimes (rarely) accidentally get kicked out of the nest, it’s also true that it’s not always an accident.
Sometimes parents simply reject offspring for reasons that are not for us to know. And that is okay. Part of honoring their wildness is accepting that they know more than us about their own lives, and that if they choose to not to support a chick they have a reason. There are exceptions of course in cases of conservation concerns, but for most backyard circumstances it is okay to accept their choice without interfering. Even if it hurts.
So please, rather than shutting down those deep feeling you have for wildlife by intervening, lean into them. Teach your friends and neighbors and children to feel those deep feelings. Because it’s from that space that we can do best by wildlife, even if it’s the kind red in tooth and talon.
It’s from there that we can grow a culture of care and empathy that shows us that nature is a community and by thinking first of community and not of the individual, can we have the broadest reach. That planting native vegetation, and keeping cats indoors, and fighting to protect land and water, is the way to love wildlife. Not by choosing who deserves to eat and who does not.
While Denali is worth visiting on the basis of its scenery alone, it’s the wildlife that will truly shape your experience. In the summer, Denali is host to some eight species of medium to large sized mammals, including foxes, lynx, wolves, grizzly bears, black bears, caribou, Dall sheep and moose. Among those, the moose, grizzly bear, caribou, wolf, and Dall sheep make up what’s known as the “Denali Big 5.”
Seeing wildlife in Denali is mostly about luck and timing, but the longer you’re in the park the more chances you have to view wildlife. As I described in my earlier post, I scheduled and bus hopped my trips in such a way that I stayed in the park most of the day. This is particularly important for moose, which are generally crepuscular, meaning they are more active in the morning and evening . Everything else is really just a gamble. Sometimes the odds are in your favor and sometimes they’re not. For what it’s worth, though, out of my four all-day trips into the park I got The Big 5 twice, both during the times I stayed primarily on the bus.
While I always left the park having experienced something new, there were definitely trips that were more memorable than others, and the range of experiences really made me appreciate the luxury of being able to go multiple times. Whatever wildlife you do have the privilege of encountering is sure to fan the flames of your love affair with this park, but I imagine for many people that affair starts first and foremost with the most visible and charismatic of Denali’s wildlife: The grizzly bears.
I took this photo in late August, just as the colors started to change.
By late July, bears across Alaska are gearing up for hibernation by entering a phase called hyperphagia, where they basically eat constantly and gain somewhere on the order of 400 pounds. In the park, their diet consists mostly of blueberries, soapberries, and roots, but they will gladly eat whatever mammals they can catch, including small rodents, caribou, moose and even other bears.
A big highlight when bear watching is seeing sows out with spring cubs. Unlike mom, the young are generally a lot darker in color, prompting people to sometimes mistake them as black bears. Observing cubs playing, foraging, and trying to keep up with mom is definitely the kind of experience that will make you wonder if you were somehow transported, Truman style, to some kind of nature documentary, but in the best kind of way.
While I won’t pretend for a second that seeing bears ever gets old, they honestly weren’t the animal that I was most looking forward to encountering when I arrived in Denali. Maybe it’s because I’d never seen one before, or because of some deep affection instilled by decades of Christmas marketing, but something about caribou utterly charms me.
Unlike many of Alaska’s other herds, the Denali caribou do not undertake an immense seasonal migration, opting instead to remain almost exclusively within the bounds of the park year round. Unless you can travel into the interior of the park, however, you’ll have little luck seeing them in the winter.
Denali used to play host to a herd that ranged in the tens of thousands, but after decades of over hunting followed by a mysterious period of low calf survival and harsh winters, Denali’s herd has dwindled to around 2,000 individuals. Fortunately, things seem to have stabilized for the time being. I wish I had seen more before the end of the season, but I’ll never forget what it was like watching this small herd move through this painted hillside.
The ungulates that seemed to most delight my fellow visitors, however, were the moose. For all of Denali’s hooved animals fall is the rut, which means males have grown out their antlers or horns and are putting them to use in sparring (practice) matches, as they ready themselves for the violent matches to come. I only saw such behavior between moose once. They locked antlers for a few seconds and went back to grazing shortly thereafter. Unfortunately it was too far away to bother with any photos. I’ll admit, seeing a bull moose, particularly on foot, is a gripping experience. However big you imagine them to be, they’re bigger in person. The rack alone can be 40lbs.
In Denali, the stakes of these fights are high, as the moose here operate in a polygynous system, where the victor will mate with and defend an entire heard of females. In other places, moose form monogamous pairs for the breeding season.
It was early morning still when we watched this cow move her two calves across the valley. They seemed pretty wary of our bus, though her biggest real threat is the park’s main carnivorous predator: The gray wolf.
Even in Yellowstone I don’t get my hopes up about seeing wolves despite there being far more individuals there. Across the Denali’s 6 million acres, there are only 30 known packs comprising about 75 adults. You can imagine my delight then, when, as we were making our way out of the park at dusk on our first trip, we rounded a corner to see this rump trotting up ahead of us. As it happens, I had been walking the road on foot only minutes before. I probably wouldn’t have caught up with it had I not gotten on the bus, but it’s still pretty incredible to imagine that I more or less went hiking with a wolf. We must have followed this adult for about a mile. It stopped a few times, evening giving it’s signature mournful howl a before it disappeared off the side of theroad. Honestly, that would have been enough for me, but our second to last trip had something really special in store.
I had heard whispering about wolf pups back at our housing campus but I never thought much of it. I figured that was deep interior kind of stuff, the kind of trek our field schedule just wouldn’t permit. So while I figured it was something exciting when we arrived at a jam packed road, I just wasn’t picturing this…
Cue total F-ing meltdown on my part.
This pup was born sometime mid-may to the single male and female that comprise the Riley Creek West pack. By around four months the pups start venturing away from their den site. Lucky for us, for a few day stretch the area they were exploring was right near the road by Toklat. After a few days, they moved away from the road, which was no doubt for the best.
The last animal I have the great pleasure to highlight is the most iconic of Denali’s wildlife. In fact, it was this animal for whom the park was dedicated. The endemic Dall sheep.
In 1906, hunter and conservationist Charles Sheldon noticed a worrying decline in the Dall sheep favored by hunters. He feared that without protection, they would be hunted to extinction. Now this is an all too familiar concept, but coming off the heels of the “era of abundance” this was actually a revolutionary way of thinking in western culture. Until 1900, colonists/settlers in the United Stated hunted without regulation and, seemingly, without much thought or worry as to the integrity of ecosystems. As a frame of reference, the field of wildlife management wouldn’t come onto the scene for another two decades.
Sheldon, however, had the foresight to recognize that something must be done and set out to establish Denali as a national park. It took 11 years, but in 1917 Woodrow Wilson signed the bill into law. Since that time Dall sheep populations rebounded and are currently considered healthy.
Despite their robust numbers, however, most of my experiences of seeing Dall sheep in the park were “technical”. As in, “technically those white specks on the mountain side are Dall sheep”. So on our last day as we traveled out of the park, I couldn’t believe my eyes when a ewe and her lamb were jogging down a hillside close enough that you could judge their forms as Dall sheep even with your naked eye. For the minute or so that we were able to watch them, I felt myself overcome with equal parts joy and despair. I was profoundly grateful for the gift of such beauty and yet so sad that once again its integrity is under such threat.
Driving home one night, my fellow passengers and I shared our backgrounds and motivations for visiting the park. Some came to experience mammals the size of which dwarfs anything in their native country, some were fulfilling missions to visit all the National Parks, while others had arrived with a spirit of adventure and little else. Together, we marveled at the unforgettable things we had seen and shared our anxieties that future generations may not be so lucky. We discussed our anger and disappointment (or among some of the foreign tourists utter bafflement) at the US government’s unwillingness to act more effectively on climate change.
One hundred years ago someone looked at this land, recognized that change must be implemented, and fought for over a decade to convince congress that in fact wild spaces and wildlife mattered enough to act. As a result, my fellow passengers and I got to see and experience things that will bring us joy the rest of our lives. The question now is whether we will wage our own fight for the future, or if we will watch from the sidelines as it turns to ash in our warming world.
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For information about climate change in the arctic please visit the following resources
It can be hard to imagine crows as anything but ubiquitous. During winter across the country, dusk marks the time where some cities see their skies turn black with thousands, even hundreds of thousands of American crows converging to roost. These crows have taken nearly all that people have thrown at them: deforestation, mass waste, and the urban sprawl that simplifies previously complex ecosystems, and uses it to their advantage. Not all species of crow have thrived in the Anthropocene, however.
Thousands of gather accumulate in the skies above UW’s Bothell campus in the winter
Far from being icons of the ultimate adapters some species of crow represent some of the most endangered animals in the world. Among those, the ‘Alalā or Hawaiian crow, is arguably one of the rarest birds on earth. Once locally abundant in the forests and woodlands of Hawaii’s Big Island, their decline began in the 1890’s following persecution by coffee and fruit farmers1. Back in September, 2015 there remained only 114, all living exclusively in captivity giving them the unenviable title of ‘extinct in the wild’. How can one species thrive with such zeal while another holds on by a thread?
Island species are generally more specialized and therefore more sensitive to human induced changes. In fact proportionally, islands host a higher number of endangered or extinct species than continental areas2. In Hawaii alone, 77 different species of endemic birds have gone extinct since the arrival of the Polynesians 2,000 years ago4, all largely for similar reasons: habitat destruction and invasive species.
Unlike their generalist, continental counterparts, the ‘Alalā is more specialized to feed on understory fruits and nuts and in fact were key seed distributors for many of Hawaii’s native plants. Island living also fostered a similar behavior seen in only one other species of crow: tool use. Like the New Caledonian crow, the ‘Alalā is a dexterous tool user, though the two species are only distantly related. Scientists believe this example of convergent evolution is fostered by aspects typical of islands, namely low predation and low competition for embedded food5.
Unfortunately, limited distributions and higher specialization also meant their population was more fragile than that of continental crows. Logging, agricultural development, loss of native pollinators, and alterations by non-native ungulates challenged both food acquisition and breeding habitat. Introduced diseases such as avian pox, malaria and the Toxoplasma gondii parasite carried by cats further weakened an already ailing population6,7. Invasive predators including rats, mongoose and cats consumed eggs, nestlings and fledglings. Finally, humans continued their tradition of persecution, particularly feral pig hunters who would shoot the birds before they could alarm call and scare off their prey2.
Together, these threats set into motion a decline in population we failed to recover despite some increases in research and management starting in the 1970’s. The last known wild egg was laid in 1996, and the last wild pair was seen in 20022,3. Some people did recognize the urgency of their decline prior to 2002, however, and a captive breeding population was started successfully rearing over 90 birds8. Although such a small number of breeders may raise red flags with respect to inbreeding and genetic depression, this is rarely as big of an issue as is commonly perceived. Unfortunately, light management and depredation by the also endangered Hawaiian hawk (‘io), decimated the released population and reintroduction efforts were halted in 1999 until a larger captive population and better management strategy could be devised.
Since that time, the ‘Alalā Restoration Project (collaboration between the State of Hawaii, the U.S. Fish and Wildlife Service, and San Diego Zoo Global) has spearheaded captive breeding programs on Maui and the Big Island culminating in a population of over 100 birds. An important part of these captive breeding programs is the use of puppets, which help prevent habituation to humans9. In addition, intensive management operations have taken place to ready their prospective home at the Pu‘u Maka‘ala Natural Area Reserve including the removal of invasive/feral animals, erecting exclosure fencing, and constructing a sort of half-way house to help ease the birds into life in the wild. These efforts have not been without setbacks, however. Back in June, 2015 two miles of protective fencing was cut down by vandals, though their motivations remain unknown.
A human dressed as an ‘Alala feeds captive reared nestlings. Photo c/o San Diego Zoo Global
Finally, after so much work, the end of 2016 marked the first time researchers and managers agreed the elements were in place for a reintroduction effort. On December 14th, five male birds were released onto the reserve, marking the first time the ‘Alalā set claw into the wild since 2002. Sadly, within weeks all but two had died. Two were killed by the native Hawaiian hawk or ‘lo, and the third was killed by “natural circumstances” which, I’m guessing, is related to a heavy storm that occurred shortly after their release. As a protective measure, the remaining two were recaptured until the results from the necropsies are obtained.
While clearly disheartening, early hiccups in a release effort like this are not unusual and conservationists and biologists are not losing hope that success is still possible. Part of ensuring such success, however, is undoubtedly public support particularly with respect to maintaining the strength of the Endangered Species Act and support of the ‘Alalā Restoration Project. The perception that all crows are alike or that generous populations of American crows means protections for other corvus species is unwarranted or redundant will be a disaster for these rare birds. So make your voice heard when funding for conversations efforts come under fire, and share your passion for endangered corvus species with friends and family. The fate of the world’s rarest crow quite literally depends on it.
Two newly released ‘Alalas peer around their new surrounding in the Pu’u Maka’ala Natural Area Reserve. Photo c/o the San Diego Zoo Global
Faike, E. 2006. Wild voices in captivity: the date of the ‘Alala. Birding 38: 64-67.
Banko, P. C.; Burgett, J.; Conry, P. J.; David, R.; Derrickson, S.; Fitzpatrick, J.;
National Research Council (US) Committee on Scientific Issues in the Endangered Species Act. Science and the Endangered Species Act. Washington (DC): National Academies Press (US); 1995. 2, Species Extinctions. Available from: https://www.ncbi.nlm.nih.gov/books/NBK232371/
Rutz C, Klump BC, Komarczyk L, Leighton R, Kramer J, Wischnewski S, Sugasawa S, Morrissey MB, James R, St Clair JJH, Switzer RA, and Masuda BM. (2016).
Discovery of species-wide tool use in the Hawaiian crow. Nature 537: 403-407 doi:10.1038/nature19103
Maxfield, B. 1998. Wild ‘Alala population suffers major setback. ‘Elepaio 58: 51.
Liebermann, A.; Nelson, J. T.; Simmons, P.; Unger, K.; Vitousek, P. M. 2003. Draft revised recovery plan for the Alala (Corvus Hawaiiensis. US Fish and Wildlife Service, Portland, OR, USA.
Lieberman, A. C., Kuehler, C. M. 2009. Captive propagation. In: Pratt, T. K.; Atkinson, C. T.; Banko, P. C.; Jacobi, J. D.; Woodworth, B. L. (ed.), Conservation Biology of Hawaiian Forest Birds: Implications for Island Avifauna, pp. 448-469. Yale University Press, New Haven.
Valutis LL, and Marzluff JM. (1999). The appropriateness of puppet-rearing birds for reintroduction. Conservation Biology 13: 584-591
Since the nineties, Avian Keratin Disorder has been an increasingly common disorder among Alaskan and PNW crows, chickadees (~17% of northwest crows1, ~6% of black-capped chickadees2) and a handful of other species, that causes gross deformities of the beak such as elongation, curvature or crossing. I’ve written previously about the details of this disease before, but at that time there was little progress in determining the underlying source of the outbreak. While AKD can be caused by a variety of things, at the scale it’s being observed now scientists questioned if there was a more consistent underlying factor. Since AKD can cause discomfort or even death (primarily through the inability to feed or preen) understanding what might be the source of this outbreak has clear management and conservation implications.
An AKD-afflicted American crow in Seattle, WA.
Among the initial suspects were environmental contaminants such as heavy metals, organic pesticides, and toxic environmental pollutants like PCBs, PCDDs, and PCDFs. Blood work done on afflicted Northwestern crows, however, showed no significant difference in the 30 blood elements tested compared to unaffected adults or juveniles3. Fortunately, new research may finally be shedding light on what’s going on.
Disease can be an easy thing to rule out if you know what you’re looking for, but new to science pathogens can evade traditional diagnostic techniques. To account for this, a team of USGS and university scientists conducted a sequencing study comparing pooled RNA of healthy and AKD positive chickadees, crows and nuthatches in attempt to identify a candidate pathogen2. Their work appears to have paid off, revealing evidence for a new picornavirus (a family of viruses previously known to science) they are calling poecivirus. Whereas 100% of AKD-affected birds (23 subjects) tested positive only 22% of the 9 control individuals did.
Alaskan black-capped chickadee with severe AKD. Photo c/o Martin Renner
Given these small sample sizes, it’s too early to throw our hands up in complete relief of having identified the cause of the AKD outbreak, especially since there’s still much to be done in understanding the potential relationship of this new virus to the environment. Nevertheless, these findings offer some insight and hope that scientists are on the right track. With more dedicated work we may soon have a much better understanding of this novel pathogen, its link to AKD, and management options moving forward.
Literature cited
1. Van Hemert C, & Handel CM. 2010. Beak deformities in Northwestern crows: Evidence of a multispecies epizootic. The Auk 127: 746-751. doi: http://dx.doi.org/10.1525/auk.2010.10132
2. Zylberberg M, Van Hemert C, Dumbacher JP, Handel CM, Tihan T, and DeRisi JL. 2016. Novel picornhttps://wordpress.com/post/corvidresearch.wordpress.com/3363avirus associated with Avian Keratin Disorder in Alaskan birds. mBio 7 doi: 10.7589/2015-10-287
3. Van Hemert C, Handel C. 2016. Elements in whole blood of Northwestern crows (Corvus caurinus) in Alaska USA: No evidence for an association with beak deformities. Journal of Wildlife Diseases 52:713-718 doi: http://dx.doi.org/10.7589/2015-10-287
I’ve talked before about how the claim that crows (and ravens) are “destroying the ecosystem and songbird populations” is mostly unsupported by science. Breeding plovers and desert tortoises are among the handful of exceptions1,2. Nevertheless I still see, even in the comment threads of this very blog, people claiming that corvids are out of control and have no predators. If it wasn’t such a misguided and ultimately dangerous sentiment I might just ¯\_(ツ)_/¯ whenever folks claimed that crows and ravens have no natural predators because those of us who spend even a small amount of time observing them in the summer will know this is anything but true.
Eggs and baby birds are a key summer food source for lots of animals and, while seeing a downy little gosling in the mouth of an arctic fox makes me cringe a little, knowing a healthy population of breeding birds is helping to sustain a community of predators is the kind of ecological balance that, in the long run, makes my heart sing.
Stillframe from Planet Earth
Corvids are part of this system too, which means their babies are also getting eaten. Usually it’s by things like hawks, eagles, owl and racoons but a recent video taken in Alberta shows yet another predator we can bear in mind. It’s never gonna be fun to see the birds I care about taking a hit like this, but knowing that corvid babies are helping to sustain top predators only deepens my love and appreciation for them. Predators and prey make the world go round and corvids have the badass role of being both.
Photo: Linda Powell
Literature cited:
1. Johnson, M. and Oring, L.W. 2002. Are nest enclosures and effective tool in plover conservation? Waterbirds 25: 184-190
2. Kristin, W.B. and Boarman, W.I. 2003. Spatial pattern of risk of common raven predation on desert tortoises. Ecology 84:2432–2443
corvidresearch.blog 