Sunday, April 22, 2012

Flipping Crabs and Other Games Naturalists Play

 [Male Horseshoe Crab, tumbled by a strong wave, struggles to right itself. Male crabs wait for females at the surf line, a risky business. Norbury's Landing, NJ today.]

Now that the Delaware Bay water temperature is approaching 60 degrees F. (it is 56.8 degrees as of 11:00 a.m. today at the Brandywine Shoal Light), Horseshoe Crabs are beginning to move into the shallows, and some spawning has already occurred, evidenced by excavated "nests" and upended crabs left after high tide.

Yesterday at low tide we walked from Norbury's Landing about a mile north along the bay, finding many upside down but still alive crabs. Many of these had broken or injured tails, as you might expect, since the tail is key in helping them right themselves after being tumbled. Gulls preyed on some, and we found a few with their blue blood pooling in the shell, while others lay dead and surrounded by pieces of gills and other innards picked away by the scavengers.

We made a project of flipping every crab right-side up along the way, a task easily done without bending over by using bare feet. Once flipped, those still strong enough immediately dug down into the wet sand to moisten their gills. A few even began the trek down the slope of the beach to the water. After "rescuing" well over 100, at least until the next tide, it was gratifying to look back down the beach and see the world rightside up, for once. Will it make a difference? Well, it did to the ones we flipped.

This morning I went back to the bay to take pictures, and found more good Samaritans on duty with the crabs left by last night's high tide.

Without much in the way of serious birding, I added a bunch of year birds the past few days, from a pair of Green Herons flying across the Garden State Parkway on the way to work (me, not them) to Ovenbirds which now seem to be singing from every wood, to "Eastern" Willet and Caspian Tern at Forsythe NWR and Short-billed Dowitcher on the Bay and a solitary Black Skimmer loafing on Nummy Island. The six Whimbrel at Shellbay Landing would have been year birds had it not been for the outrageous wintering bird we saw during the Cumberland Christmas Count on January 1. Yesterday while cycling I heard a Northern Parula at Cox Hall Creek WMA, and a Prairie Warbler down along the Cape May Canal, two more FOY's (First of Year).

A bit of foreshadowing: listen to Carolina Chickadees much? Ever notice how their songs vary? Ever notice where in southern NJ their songs vary? It's something I've become curious about. . . .

I like birds well enough, but nature paints too broad a brush not to look elsewhere. Witness:

[This Rough Green Snake at The Nature Conservancy's Lizard Tail Swamp preserve was the first one I've ever seen alive - a few roadkills in Belleplain and elsewhere seem to suggest they are more common than one would think. But they are arboreal, and a small green snake in a green tree is mighty hard to spot. It took a sharp-eyed friend to pick this one out. There are two "green" snakes, the other being Smooth Green Snake, a more northern, hilly-area species not known from Cape May county. I always forget which is found where - thanks, Vince, for reminding me! It also helps to look closely. Although this Rough Green Snake does not have keeled facial scales, if you squint you can see a little line at the center of each scale farther down the body, hence "rough." Keeled scales can be a useful i.d. point for other reptiles, e.g. Black Racers have smooth scales while Black Rat Snake scales are keeled.]

 [Northern Fence Lizard, also at Lizard Tail. Besides on their namesake fences, look for them sunning at the base of trees.]

How great would it be if reptiles were as viewable as birds? We are lucky, in NJ, by the way, to have a great state guide to reptiles and amphibians: Field Guide to Reptiles and Amphibians of New Jersey, by Vicki Schwartz and David M. Golden. Highly recommended, as is the companion CD to frog vocalizations.

[A look at this Question Mark's shadow tells you it was trying to maximize the solar energy it was absorbing, catching all the sun it could. Lizard Tail Swamp last Thursday.]

[Wild Lupine in bloom, typically, on dry sandy soils in Lizard Tail Swamp preserve last week.]

[Different individual birds of the same species can often operate on different schedules. This Killdeer at Forsythe NWR still has 3 weeks of incubation to go before her eggs hatch. Right along a path at the refuge, she has become tolerant of people but for some reason jumped off the nest and began the famous broken-wing distraction display when I walked past after work one day last week.]

[In comparison, a Killdeer pair at the Wetlands Institute in Stone Harbor already has hatched young, including this little guy which called softly but not unlike mom and dad. The single breast band (adults of course have two) could lead the unwary to call this a Semipalmated Plover - one with wrong shape, too long legs, too long, wrong-colored bill, and of course, one in downy plumage. A mistake that should not be made - but it's been done.]

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