In late February, on a cold, breezy day with occasional snow flurries, I traveled up to the shore of Lake Erie with my advisor Dr. Tonra, and fellow grad student Kristie Stein, to erect 30-foot high automated telemetry towers. Hard to believe in those weather conditions, but some of the first north-bound migrants were already starting to arrive in northern Ohio. Rusty Blackbirds (affectionately known as “Rusties”) are early migrants, with many birds leaving their wintering grounds in the southeast U.S. in early March. So while Alicia was happily tracking “wintering” Swainson’s Warblers in sunny Jamaica (see her post below), I was gearing up for “spring” migration in frigid Ohio – I swear I’m not jealous.
Seriously, despite their meteorologically inopportune migration timing, Rusty Blackbirds are actually a really cool species, and it’s well worth braving the cold to learn a thing or two about them. A once abundant species, their numbers declined drastically throughout the 20th century, and they are now a species of conservation concern for many states and Canadian provinces. Rusties breed in wetland areas of the boreal forests, and winter across the southeastern U.S. around bottomland hardwood swamps; my research on the species takes place in the time between, during migratory stopover events in spring and fall. The Western Lake Erie Basin, specifically Ottawa National Wildlife Refuge and Magee Marsh Wildlife Area, has been identified as a migratory hotspot for the species, and thus a great location to learn about their migratory behavior.
The objectives of the season are easily stated: deploy 30 radio transmitters on Rusty Blackbirds, track them daily to find foraging locations, perform vegetation surveys at these locations to learn about their habitat requirements during migratory stopover, and continue tracking these individuals until they depart the study site. After getting the telemetry towers up and running (more about them later), the next order of business was capturing Rusty Blackbirds, which I did successfully on March 15 with the help of fellow grad student Elizabeth Ames and field technician Kellene Collins. The nanotag radio transmitters I deployed on Rusties are all on the same frequency, but each has a unique digitally encoded identifier, so when I track them with a handheld receiver, I can follow multiple individuals at once if need be. These tags are especially handy for use with the automated telemetry towers. The towers are set to scan continuously on one frequency, detecting all tags on that frequency. We operate 10 towers around the study site and spread across Western Lake Erie, as far north as Detroit River International Wildlife Refuge in Michigan, so we can get accurate estimates of departure times and track the large-scale movements of birds after they depart the immediate study area. The tags I use may also be detected by the much larger Motus array of towers, operated by Bird Studies Canada, which will allow us to follow the approximate paths of individuals even beyond their departure from Lake Erie.
Once I got the first tag deployed on March 15, we were off and running, with more tag deployments a week later, and then on April 10th, 12th, and 19th. Between deployments, Kellene and I were constantly tracking individuals and performing habitat surveys, as well as downloading (and troubleshooting) tower data. And aside from a cold snap and snowstorm in early April, the weather mostly cooperated!
Even before any extensive analysis, the data have given us several interesting surprises. First of all, stopover duration was much longer than expected for spring migrants, with many birds remaining for well over 3-4 weeks. Secondly, perhaps related to the long stopover duration was the presence of a migration molt in nearly all captured birds. We knew that most Rusty Blackbirds undergo a partial pre-alternate molt on the wintering grounds, but we did not expect so many birds to still be in such heavy body molt in the middle of their migration; perhaps the completion of this molt is the purpose of the long stopover duration. Finally, we were excited to find that nearly all the tagged birds made their departure from the site at night, meaning that they are nocturnal migrants like warblers (at least in the spring). Until now it had been supposed that they migrated during the day, like other blackbird species.
My last bird to depart (the infamous 66!) waited until all my other birds had been gone for several days before he finally made his night flight on the evening of May 16, for a minimum stopover duration of 28 days. I returned home to Columbus the following day, where I’m now helping Elizabeth Ames and Kristie Stein in their respective field seasons, studying Prothonotary Warblers and Black-crowned Night Herons. Long live field work!
Greetings from Jamaica! I am happy to say that I call this sunny tropical island my home for almost five months. It's the perks of conducting tropical conservation field work, but it still feels like a dream every day (besides the seed ticks, those are things of nightmares). I am excited to share what I have been up to for the past two and a half months!
When Dr. Tonra and I arrived in Jamaica in the beginning of January, our goal was to capture as many Swainson's Warblers as we possibly could. These birds are notoriously sneaky. Their drab plumage and ground foraging habits lend to them being almost impossible for birders to spot and one of the most difficult of the North American birds to research. We knew it was going to be a challenge. With the help of Bryant Dossman, a Cornell Lab of O/Smithsonian Migratory Bird Center Ph.D. student working on American Redstarts, we scoured the forest for individual Swainson's Warblers using vocalization playback. Once we found some responsive individuals, we target netted each bird with a lot of success, and of course a lot of frustration!
The Swainson's Warblers we have caught are equipped with radio transmitters (as seen in the photo above on the right) and my field tech Cody Lane and I are hand tracking individuals until their departure in April. I will calculate home ranges for each bird and habitat data that we have gathered such as soil moisture, shrub and canopy density, leaf litter composition and arthropod abundance will be used to determine how they utilize their habitat. I am interested in how these birds can track moisture throughout the season and if they will be able to adapt to the climate change induced reduction in rainfall in the Caribbean. Being a species that requires relatively dry forested habitats, we could see this decrease in moisture having some interesting affects throughout the coming decades. Overall not much is known about the winter ecology of this species, and being that they are a species of conservation concern, it is exciting to be gaining more insight into the birds daily behaviors. I am so excited to be able to study such an elusive species, as I am already seeing some interesting within season movements!
Field work in Jamaica can be a challenge and we make sure to take advantage of the beauty of the country on our days off. We believe that it is important to really immerse ourselves in the Jamaican culture, talk to locals about their lives and experience the food, tropical landscapes and of course, the native wildlife.
If there is one thing I love as much as getting out in nature, it is making and eating great food. So, this time of year is really exciting as the two worlds collide. This has been a fantastic year for edible fungi on both coasts, and I have been taking advantage all I can. (NOTE: never eat wild mushrooms without being ABSOLUTELY sure you know what you are eating, always use a field guide, and be well aware of POISONOUS lookalikes).
While wrapping up our Fall field season on the Olympic Peninsula, I was treated to a fantastic year for the golden chanterelle (Cantharellus cibarius). This beautiful mushroom is recognized by its color and the shallow, more wrinkled than gilled, hymenophore (the structure that bears the spore producing cells) that runs down the stem. In addition to being quite tasty, they are extremely good for you, as a great source of Vitamins C and D (one of the highest natural VitD concentrations known!), and potassium. Always beware of the TOXIC false chanterelles (Hygrophoropsis aurantiaca), scaly chanterelle (Gomphus floccosus), and other lookalikes.
Along side those beauties were the similarly tasting, yet firmer, hedgehog mushroom (Hydnum repandum), which is best identified by the shaggy, toothed, hymenophore that gives them their common name. Hedgehogs have a golden cap and stout scaly stem. They are the fruiting body of a mychorrizal fungus. This means they form a mutulaism with their host tree, gaining carbohydrates from the tree while making important minerals available to it. In the west, hedgehogs are often found along with chanterelles in moist Douglas fir/hemlock forests, like where I found them on the Sol Duc River. These two Northwest treasures made for an incredible wild mushroom pizza with a creamy pecarino romano bechamel sauce (pictured). I wish I could eat it every day.
After returning to DC, I went for a walk in Rock Creek Park, just down the block from our home, and found a spectacular patch of chicken-of-the-woods (Laetiporus sulphureus) on the way in. This is a shelf fungus that grows on damaged and fallen trees. We found this patch on an old fallen white oak (Quercus alba). Unlike many shelf fungus that grow a permanent fruiting body, chicken-of-the-woods often grows back year after year. Unfortunately for live trees, chicken-of-the-woods can ultimately rot a tree to the point of death as it consumes its tissues. This is an important ecological function however, as dead and fallen trees provide a lot of wildlife habitat. The fungus has a flat, porous, bright yellow hymenophore and a bright yellow-orange upper-side. They are quite beautiful, and they do have the texture and lemony taste of chicken! Cooking with them requires liquid, as they can be quite dry and drink up a lot of oil/butter. We prepared a delicious soup with chicken stock (of course), heavy cream, onions, garlic, fresh herbs, and some dry sherry (pictured).
Hope to find more in what remains of Autumn, a wonderful way to enjoy nature outside and on the table!
All photos, unless otherwise noted, are © Christopher M. Tonra, all rights reserved