Ox beetles and other monsters

An Ox Beetle. Taken July 7th in a grassland in Ocean Co., NJ.

This (if my ID books and bugguide.net have steered me right) is an ox beetle (Strategus anteus). I've seen a lot crawling around sandy bare areas of my Ocean County grassland lately. It is one of 5 ox beetles (Strategus sp.) in the US and the only one (at least the only common one) that lives in the Northeast. Bugguide.net shows it going all the way up to Nantucket Island in Massachusetts. Females (which lack horns) lay eggs in rotting wood, where the larvae develop. Male horns probably serve as some sort of courtship or mate-getting ornament, which is amusing to picture!

 Another big beetle (Pasimachus sp., ground beetle family) common in my Ocean Co. grassland. This is a flightless beetle (shell is fused in the middle)! I've found shell remnants below Amercan Kestrel feeding perches. (Photo taken June 22.)

The sandy soils of south Jersey seem to support lots of really big insects. I've seen several other kinds of 1-2 inch beetles (including other dung beetles) crawling around between the grass tufts. Along with the abundance of over-sized grasshoppers, they seem to provide a main source of food for American kestrels (see here and here), and also possibly nighthawks which are common in the Pinelands and apparently eat a lot of beetles...this according to their BNA account and this wonderful Audubon print...

Beetle-hawks 2

Elytra (shell) from a large Pasimachus ground beetle found with pellets near an American Kestrel feeding post.

This beetle shell was found near (a few feet away from) an American Kestrel feeding post in Lakehurst, Ocean Co., NJ (taken June 22nd). I moved it over for composition purposes, but I'm pretty sure the kestrel ate it (note the pellets with insect bits in them). Also it has a hole in it that I could picture a kestrel's beak tip going into. Below is (I think) the same beetle species found dead about 50 feet away from the post. According to bugguide.net, it's in the genus Pasimachus, in the family Carabidae - the ground beetles. This adds weight to my theory that summer kestrels are as much beetle-hawks as they are vole-hawks, or sparrow-hawks. And I guess they are grasshopper-hawks, too, as I found a large grasshopper wing nearby, as well. See previous post on beetle-hawks here.

Thanks to bugguide.net I know that these big monsters are in the genus Pasimachus (Family Carabidae, the ground beetles), and that it is a flightless species, having wing shells ("elytra") that are fused in the middle.

A foot-trembling woodcock?

I had one of those encounters today where you meet a bird and then think "why aren't you running away from me?" (And luckily had a camera with me.) This nice woodcock allowed me to park my car right next to her while she went about her business. This business was actually the interesting part: instead of probing over and over to look for worms, she appeared to be feeling with her feet! In a rocking-back-and-forward motion, she would put a foot down twice before putting her weight on it and advancing one step to do the same with the other foot. 

Other shorebirds, especially Charadrius plovers, but also solitary sandpipers and others, use a "foot trembling" foraging technique that apparently helps scare inverts up to the surface. To quote one paper on foot-trembling in the semi-plover (Cestari 2009): 

• Tapping or trembling movements involve the use of one leg at time during foraging in order to expose or incite movement in cryptic invertebrates of intertidal zones and grasslands (Sparks 1961, Piersma 1996). The advantage of this technique lies in the transfer of vibrations from the foot through the substrate to the prey (Tarburton 1989). This kind of movement may also startle insects on the surface, facilitating the capture of prey by visual-foraging birds (Piersma 1996, USFWS 1996).

This sounds a lot like what I observed, and woodcock are "shorebirds" after all. (What a bad name for this group of birds.) ... But wait, after checking the Birds of North America account, I discover that alas I'm not the first one to observe this rocking, foot-feeling walk, although it does still seem to have some mystery associated with it. From the BNA account (Keppie and Whiting 1994):

• While feeding on lawns, birds seen to rock their body forward-backward without moving the head, as they slowly walk about, placing weight heavily upon lead foot. Does rocking motion and heavy foot generate vibration that causes shallow earthworms to move, a response then heard by woodcock (Marshall 1982b) or detected by its bill in contact with soil? Fascinating anecdotal reports in early literature suggest this may be so (Pettingill 1936).

Maybe so. I should have watched longer instead of getting greedy for photos!

Beetle-hawks

A sparrow-hawk? No, a beetle-hawk.
 

Two pellets (a.k.a. puke) freshly coughed up by American kestrels (they were still moist...note the ant). Also part of a dismembered iridescent beetle (a scarab?). All were found beneath favored kestrel feeding posts in an Ocean County (NJ) grassland. Almost all the kestrel pellets I've found so far this April have pieces of beetle shells in them. I think there are lots crawling out of the soft sandy soil -  maybe as hibernating adults, or maybe freshly-metamorphosed from wriggling, dung-fattened grubs. Some they are definitely catching on the ground, but I wonder if some of the aerial insect hawking I see them doing (way high up) is after these big and tasty slow-flying beasts. The pellets are about 1 inch long, for scale.

Notes from a frozen river # 2

Slushy ice in the still-not-completely-frozen Musconetcong River, this despite single-digit nighttime temperatures. Tonight is supposed to be minus 8! I watched a deer wade across it (apparently comfortable) yesterday.

Fox tracks and pee at a rose-bush that doubles as a scent post.
 

A mouse highway between two rose-bush clumps.
 

 

Barberry berries are still around. Something must eat these because it spreads all over. But they can't be very tasty if they are still around at this date.

A crew-cut of spice bush sprouts, munched down by deer. This (plus all the thorny invasives dominating the shrub layer) is a sure sign of over-abundant deer. 

This hermit thrush was hopping around the cliff-side and eating multi-flora rose hips. It was a good bird morning. Also seen: winter wren, yellow-bellied sapsucker, field sparrow, pileated woodpecker, brown creeper.

Chickadees and cherries

Wild black cherry trees are in full fruit these days, and the birds are all over them. I found a good one a few days ago in Lanoka Harbor, NJ. Good in this case = low to the ground, and absolutely loaded with ripe fruit. The "low to the ground" part facilitated nice views of the birds perusing the fruit clusters, and the "loaded" part made the birds crazed enough with food lust that they paid little attention to me. Orioles, titmice, and house finches all picked at the cherries, and a gnatcatcher hopped about, maybe in search of cherry-eating insects. A juvenile chipping sparrow, a female cardinal, and a few robins also made appearances.

But the star of the show (both in numbers and in style) was a flock of about 10 carolina chickadees. Their strange eating style was as follows: pick off a cherry, grasp it between the toes, peck at it for a second, drop it, and move on to the next. I thought maybe they were eating the pit, at first...similar to how sparrows often eat just the seeds of rose hips, spitting out the fruit.

Chickadee, pecking.

But when I downloaded my photos, I found a surprise: a little grub-like creature. My guess is that they were extracting fly larvae, and then spitting out the "useless" fruit and pit which would clog up their guts with empty calories. The amazing thing was how fast they would accomplish this process: pick, peck, drop, repeat.

Chickadee in mid-grub-extraction. Notice the squirt of juice!

As with many great discoveries, I have no proof but a grainy image. It was getting dark, and I didn't have time go cherry-dissecting to find grubs. I did, however, find time to eat a few myself.

Exhibit A. Grainy close-up of a grub-like object in the chickadee's beak.

Wild birdseed

Deer-tongue grass (Dichanthelium clandestinum).

"Shall I not rejoice also at the abundance of the weeds whose seeds are the granary of the birds?" - H.D. Thoreau

Today I found a flock of 25 bobolinks gorging on seeds in a patch of grass (below). It reminded me that wild seed bonanzas can rival birdfeeders in quality and quantity. The bobolinks, plus about 10 savannah sparrows, were confined to a patch of one particular type of grass, a native species named deer-tongue (Dichanthelium clandestinum). It is recognized by its fat leaves, hairy stem, and seeds hidden within a tube at the top of the plant (hence the "clandestine" species name, I guess). The birds were flying from plant to plant, voraciously picking the seeds out of the tops. It reminded me of another natural spectacle: the multi-species bird parties that occur in a fruiting red mulberry tree in June. Always more satisfying to watch (for me) than a bird feeder for some reason.

Bobolinks at the "feeder."

Later in the day, I came across two more bird parties. One, again, in a patch of deer-tongue, and another in a patch of different native plant: lamb's quarters (Chenopodium album). The lamb's quarter party was less diverse - consisting only of savannah sparrows - but it was just as hopping.

Lamb's quarter (Chenopodium album).

The savannahs were obviously quite happy gorging themselves on the seeds, which are quite a bit smaller than deer-tongue's, and in fact look like tiny black specks.

The small but tasty seeds of lamb's quarters.

They are apparently nutritious...to humans too. Wild food guru Euell Gibbons recommends grinding them into a hearty flour. (As a side note, I happen to know that the leaves are also much relished by real lambs.) Mixed in with the lamb's quarters was another native (though often disparaged) birdseed-bearing plant: ragweed. The birds will have to wait a while for this one, however. Right now it is still in the pollen-spewing (sneeze-inducing) flower stage.