Inside the Outdoors: Early Migrants Take Big Risks – Pine and Lakes Echo Journal

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Late on Saturday afternoon, less than 24 hours before the official arrival of spring, I heard the familiar notes “cheer up, cheer up, cheerfully” from my first robin of the new season. . I had not heard this call since last November, when the last recalcitrants left for more temperate places to spend the winter.

Some bird voices are unmistakable, and the robin’s is one. It may not be fully appreciated due to the abundance and familiarity of the robin. But when it hasn’t been heard in months, and it’s tied to the end of winter, it sounds all the more musical.

I am not a phenologist, one of those people who record the timing of events in nature so that they can be compared from year to year. So I cannot say precisely how the arrival of this robin compares to the spring of 2021. More easily remembered are the climatic conditions of a year ago, and the low snow cover of last winter. This winter was very different. Despite the recent wave of above average temperatures, there is still a blanket of snow almost everywhere. The ground is still frozen, so the prospect of a robin finding its favorite meal – earthworms – is remote. Yet there was this robin, perched on a snowdrift, singing a song to announce its return.

I remember a TV ad advertising a service to help you sort out your own ancestry. Its aim is to fill in the gaps in your knowledge of who you are descended from and – with many of us having immigrants from Europe or elsewhere somewhere in our origins – where in the world we come from. “I want my kids to know they come from brave people,” the spokesperson tells the camera in this ad. “They took risks, big risks,” she says, as a clip from the film shows a sailboat on a forbidden stretch of ocean.

Migratory birds also take risks. Big risks. Not the least of them, aside from collisions, predation, and other threats that come with long journeys to wintering grounds, is when they return here. Nature has programmed in them an irresistible urge to aggressively pursue the most important priority of their lives, which is to secure a territory, find a mate, and raise the next generation of their species.

One would think that such an early arrival would not be necessary, given the number of good weather months before autumn. But raising nestling songbirds to adulthood is fraught with dangers, ranging from nest theft to red squirrels, blue jays and crows, prowling cats and even some species of hawks. Sometimes an entire nest is lost. Even when a brood is successfully hatched, mortality is high; about 80 percent for robins. For this reason, robins usually raise more than one brood per season to compensate for their high mortality.

Photo illustration, Shutterstock, Inc.

Thus, the premium for an early start. But the survival of “veteran” adult birds is not assured at this time of year, especially in the northern regions of the state. Most of the landscape is still frozen. The abundance of insects is weeks away. Forage options are limited and consist of seeds and wilted fruit that might remain on shrubs and trees from last fall, or that can be gleaned from snow-free patches of ground. Not the choice and abundance that would be theirs in April or May.

Then there is the very real possibility of a major blizzard in late March. It was common enough during the state high school basketball tournament that the “tournament blizzard” has become part of the Minnesota weather lexicon. Not to mention the risk of prolonged onset of sub-freezing temperatures. This too can have an impact on early returnees, like my robin who announced his arrival the day before the official arrival of spring.

Another risk-taking migratory bird is dear to the hearts of many bird hunters. It’s the American woodcock, a strange and mysterious creature that strikes both as an upland bird, like the ruffed grouse, and as a shorebird, like the snipe or sandpiper. The woodcock’s home address is this intersection where aspen and birch forest meets wetlands, the often densely cultivated interface for alders. The woodcock has a long, slender pencil-like beak that is tailor-made for probing loose soil for earthworms, although it will eat other invertebrates – insects – if given the opportunity.

But at the end of March and the beginning of April, when the woodcock arrives here, there are few earthworms or other invertebrates. A magnet for early woodcocks is moist, soft ground along streams and in places where small feeder streams flow into wetlands. These, especially if facing south, are the first places to thaw. These are the first places where earthworms will be available for woodcock.

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Photo illustration, Shutterstock, Inc.

In a pinch, the woodcock is said to supplement its favorite foods of worms and insects with seeds, sedges, and other foods on the vegetarian side of the menu. This is the time of year when they are most likely to have to temporarily make those food concessions. Some of those who hunt woodcock might actually prefer woodcock to make it a year-round habit. Their summer and fall diet is mostly earthworms, and some believe the flavor of their dark flesh resembles that of liver!

Like the robin that arrives early, wintery spring weather is known to victimize the woodcock. Heavy snowfall and temperatures that drop significantly below zero are not what the woodcock anatomy was designed for. Short spells can be survived, but not long ones. The most complete records of weather-killed woodcocks come from their wintering grounds in the south. This is understandable, given their concentration in limited habitats there. But when the woodcocks have come north in the spring and are dispersed in habitats mostly away from humans, sightings of weather-killed birds are a much longer chance. But if prolonged sub-freezing temperatures and snow cover can kill them in the south, so would they here, especially after enduring the rigors of their northward migration.

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Mike Rahn, columnist

They are not the only migratory creatures that come hard north in the wake of the retreating winter and in doing so risk a counterattack of harsh weather conditions capable of killing them. But they evolved as a thriving and prosperous species with this risk-taking habit built in. So who are we to question Nature’s plan for their survival?

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