Monday, July 25, 2011

Bird bug

Hummingbird moth (Hemaris thysbe) drinking nectar from a wild bergamot flower in my garden two days ago (Warren County, NJ).

This insect must have evolved as a "hummingbird mimic"...but why? Even the eye looks like a vertebrate eye, with a dark "pupil" in a brown "iris" (click on bottom picture). The white belly and dark back (known as "bicolored") is a common coloration among birds and other vertebrates. I think the clear patch in the wings makes them look more like the blur of a hummingbird wings. The whole package must be meant to give pause to potential bird-predatator, which presumably couldn't (or at least wouldn't) dine on a fellow bird.

Saturday, July 23, 2011


Possible "Big Dipper" fireflies (P. pyralis). Taken 8:15 PM, June 25 in Warren County, NJ. Corn may be a "biological desert" but it sure has a lot of fireflies over it, especially when it is young.

The katydids are just now starting to mean business. And of course the fireflies have been out for a while, but I've just started paying more attention to them lately.  

They begin the light show at around 7:30 PM and then (this is what I've somehow failed to notice until now) they tend to go away almost completely once it gets really dark. There also seems to be a succession of different species over the course of the twilight. The "short, upward, vertical-liners" start it out, flashing in dazzling numbers over grassy areas. Then the "J-makers" and other higher flying or tree-dwelling ones become more noticeable. The "short, upward, vertical-liner" I take to be the Pennsylvania Firefly (Photuris pennsylvanica). According to my NWF insect guide, these often fool Big Dipper Fireflies (P. pyralis) - which I take to be my "J-makers" - into landing near them by imitating their female flash pattern on the ground, and then eating them!

This link from Dr. Steven Carr at Memorial U. of Newfoundland, shows the flashing patterns of the various species.

Sunday, July 17, 2011

Ox beetles and other monsters

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

This (if my ID books and 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. 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...

Thursday, July 7, 2011

A domestic situation

Here was a curious situation. A pair of bluebirds that inhabited a box about 10 yards away from my tree swallows were actively harassing them a few days ago. The tree swallows had young in the nest at the time, and the bluebirds were still laying eggs (3 at last count). It seemed like the bluebirds were a bit tougher than the swallows, but (being in the box) the swallows were able to hold their own. I have no idea what the indigo bunting was doing...I only noticed him after I downloaded the photos!

As an aside, I've noticed birds being testier in general these days. I'm guessing that it's due to territories "expanding" while fledglings are roaming around, but still being fed by their parents.

Tuesday, July 5, 2011

Tree swallow update

Dad, peeking out the front door. (Taken June 15th in Warren Co., NJ).

At least some of the baby tree swallows in my box (concieved during this copulation event) were still in the nest yesterday (July 4th). I could hear them chirping in there, sounding pretty much like the adults. I think I saw a fledgling or two (looked like drabber versions of adult) but didn't have a chance to confirm it. Anyway they are pretty much home free and should be fledging soon. (Nestling periods lasting longer than 14 days have to be pretty rare. I know Acadian flycatchers usually go about that long, and that they are on the long side among songbirds.) So that would be about one full month from copulation (May 30th), through hatching (June 19th), to fledging (about July 4th). A bit longer if you count nest building which I didn't actually observe (I must have been away during it).

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, 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 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.