One of the most anticipated events in March for naturalists is the amphibian migration known as “big night.” With each warm evening we think we get closer to the main event, and though sometimes a big night turns out to be a little one, when the big night happens it is an event not to be missed.
The big night typically happens on the first warm and rainy night of the spring (45 degrees or warmer) when the majority of amphibians – frogs and salamanders – emerge from the burrows where they overwintered and journey back to the vernal pools they were born in, to breed. (A vernal pool is a small temporary wetland that fills with water in spring or fall.) Conditions for the big night may not occur until April, but it is a good idea to be prepared because you often don’t know if the weather conditions will be just right until a few days before it happens.
The journey may not seem very long on a geographic scale, until you consider the fact that these cold-blooded animals may be just a few inches long. Their migrations are made even more difficult since roads transect so many of the routes the animals have to follow. Slow-moving terrestrial animals crossing roads on nights with poor visibility unfortunately leads to high rates of mortality. Maine Big Night, a community science project that was started to collect data on these frog and salamander movements, reported 31.89% of the 5,732 amphibians detected during the 2021 surveys – across 185 sites with 737 hours of effort – were found dead.
But you can help. Maine Big Night is still recruiting volunteers to go out on warm rainy nights to conduct surveys and help amphibians cross safely. You can learn more about the project at vernalpools.me/big-night. Maine Big Night also has a very active Facebook page where you can learn more and stay up to date on timing of the big night: facebook.com/groups/bignightmaine. Shameless plug: Maine Audubon is hosting a program with Greg LeClair, the founder of Maine Big Night, who will talk about the project and how to get involved, on March 25 at 7 p.m. This is a free online program (sign up at maineaudubon.org/events). Whether it is becoming a volunteer, or just driving more carefully and being mindful of amphibians in the spring, any additional help can go a long way to helping these threatened animals.
WOODCOCK ARRIVAL
Slightly easier to predict than the big night in spring is the arrival of American woodcocks and the beginning of their elaborate sky dances. Male woodcocks perform these courtship ‘dances’ in the sky, typically in the evenings, showing off to onlooking females in an attempt to win one over.
If you’re lucky enough to see one, it is quite a memorable experience, which leads to a very common question we receive: Where can I go to see woodcocks display? The surprising answer: almost anywhere.
It helps to start by knowing exactly what you’re looking for. American woodcocks, colloquially known as timberdoodles, are a species of shorebird (think sandpipers and plovers) except that they don’t live by the shore. They live instead in young forests where they use their long bills to probe into the soil for invertebrates like earthworms. Spending so much time with their heads down and bills in the ground, they’ve evolved to have their eyes far back on their heads, giving them a nearly panoramic “rearview binocular vision.” To achieve this (and I’ll oversimplify for brevity of this article), the woodcock’s anatomy has changed so much that its ears (which are obscured by feathers) are below (not behind) its eyes, and its brain has essentially flipped upside down.
This is all to say they’ve got a unique look to them. In spring, after migrating back from their wintering areas in southeastern states, males waste no time to begin their mating displays by seeking out clearings in the forest or open fields.
The displays begin with a nasal “peent” that the bird calls while standing on the ground, often given for a minute or so before it launches into the air. From the air, a variety of twittering and chirp-like noises can be heard, but this is not a vocalization, it is made from air passing through specially modified outer primaries (the outermost flight feathers). Think of how you can whistle by blowing with a blade of glass in your hands. In the same way, their fast wing beats produce these unique noises. The aerial dance lasts about a minute, with the last notes becoming more emphatic as the bird quickly descends to the ground, landing very near to the spot from where it took off. These dances are typically performed at dusk and dawn for a window of 30-40 minutes, starting 30-45 minutes after sunset and 30-45 minutes before sunrise.
To highlight my point that woodcocks can be found almost anywhere (assuming you’ve got a little forest with a nearby clearing), we can look at our results of the Maine Bird Atlas so far. The Maine Bird Atlas is a project by the Maine Department of Inland Fisheries and Wildlife with a goal of documenting the breeding and wintering ranges of Maine’s birds.
It is quite hard to “confirm” woodcocks are breeding in an area, but if you hear them performing their courtship displays, this is considered a “probable” breeding status. One atlas volunteer, Jeff Cherry, got a little obsessed with proving that woodcocks were more prevalent than most people appreciated, and has since documented woodcocks breeding (mostly displaying) in every single block (a 9-square-mile survey area in the Maine Bird Atlas) in Lincoln County.
You can see our preliminary results, including the giant swath of Lincoln County, for American woodcock records at: ebird.org/atlasme/map/amewoo. Get out this spring for a little timberdoodling and report your findings to the Maine Bird Atlas via ebird.org/atlasme.
Do you have a nature question for Doug? Email questions to ask@maineaudubon.org and visit maineaudubon.org to learn more about backyard birding, native plants, and programs and events focusing on Maine wildlife and habitat. Maine Audubon leads free bird walks on Thursdays, 8 to 10 a.m., at the Gilsland Farm Audubon Sanctuary in Falmouth. (Walks will begin at 7 a.m. starting in April.)
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