Thursday, June 4, 2015

Hey June, where'd you go?

I never seem to get used to how quickly time can pass. To think that May, with all the migration and excitement it brings, is over and we are already a couple days into June is nuts. When you think of June you think summer and it brings with it the promise of freedom and vacation. The Greenhead flies are still small, the mid-day heat is still bearable, and the infamous shore traffic is still minimal. Yes, June is indeed a glorious time here in Cape May.

I spent the first day of June working on my deck, soaking in the perfect morning. My yard was teaming with life and in the span of a few hours I had over 10 species of bird make their way through my yard, including a very vocal Yellow-billed Cuckoo and a brilliant male Scarlet Tanager. I quickly became enamored by a pair of Chipping Sparrows nesting in a close Pitch Pine and watched as they diligently brought back caterpillars, flies, and other various insects. They would cautiously making their way up the branches and out to their nest, perfectly camouflaged among a cluster of pinecones. Though I never saw them, I could here the faint peeps of their chicks as they begged for the morsel of food. Yes, it was an incredible way to start the month!

Chipping Sparrow bouncing around the yard. [Photo by Sam Galick.]

So, you can imagine my shock when I walked out onto my porch Tuesday to give June 2nd a proper welcome and was greeted by a cold, wet blast. As someone who spent the past 8 years in Georgia, I don’t take kindly to the cold, especially when it’s supposed to be summer. This week has seen nearly record lows for the first week of June and I can’t help but worry for my Chipping Sparrow chicks.

Birds have various methods at their disposal when it comes to dealing with the cold. Overwintering birds, like American Goldfinches and Tufted Titmice, can acclimatize to the cold. However, acclimatization requires a gradual decrease in temperature to allow the bird’s metabolism to actually slow down, reducing their normally high caloric needs. In other words, it’s not a useful trick for sudden cold snaps. Like mammals, birds can produce frictional heat within their muscles by shivering. Also, as you may have observed, birds will fluff up their feathers when cold. This allows air to be trapped within the soft down feathers close to the skin of the bird. The air quickly warms up and acts like a blanket for the bird.

Eastern Kingbird slightly fluffed up in the rain. Depending on how long the rain may last, birds maybe be forced to forage and continue nesting despite the unfavorable conditions. [Photo by Jesse Amesbury.]

 All these adaptations work great for adult birds that are cold, but what about chicks who have no feathers and already have extremely high energy demands? Shivering, as minimal movement as it is, still requires energy and nestlings have to put everything they have towards growth and development. What makes this cold snap even scarier for our young chicks about the area is that it’s a very wet cold. Anyone who has been caught in a sudden rainstorm can attest to the fact that being wet and cold is much worse than just being cold. The risk of hypothermia increases dramatically when you’re wet, which is why wilderness survival 101 is to stay dry.

For our baby birds, huddling together is a great way to stay warm, but parents also do a lot to keep them dry and warm. Adults will sit on their nest even after the eggs have incubated and hatched in an attempt to shelter their young ones from the harsher elements. Most adult birds will also develop a brood patch during the nesting season, a feather-less area on their stomachs to allow direct skin-to-egg or skin-to-chick contact. This area of skin is chocked full of blood vessels and increases heat transfer from parent to offspring. Many perching birds only develop one large patch on their stomach, whereas shorebirds will have two patches, one on either side of their legs. Shorebird chicks are very precocial, meaning they hatch out of the egg with down feathers, open eyes, and the ability to run around on comically-large legs and feet. These chicks will snuggle up underneath Mom and Dad, against those brood patches, to stay warm and dry. Since some of our chicks are beginning to hatch on our beaches, you might start noticing fluffy Piping Plovers with extra legs!

Ospreys nesting in Stone Harbor. The female stays on the nest to not only incubate the eggs but help shield them from the rain and wind. [Photo by Travis Davis.]

Digiscoped photo of Piping Plover adult with chick hiding underneath it. Plovers are in the category of shorebirds with two brood patches, one on either side of their legs. [Photo by Lindsey Brendel.]

As I sit here looking out the window at the windy, rainy, cool weather, I am hoping for sunnier days ahead. Call me a softie if you must, but I cannot help worrying for the young and vulnerable chicks around our area. If the forecast holds though, it looks like we are on the tail end of this less-than-desirable weather and we can get back to summer and the June we all know and love.

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