Migration and the Great Lakes

Check out how birds largely avoid moving over the Great Lakes. It's most apparent in birds moving across the Niagara Peninsula between Erie and Ontario. It's not a problem of coverage, you can see weather moving across Superior and Michigan.

Migration and weather

The migration pattern on radar is a lot different tonight than several nights ago. Take a look at tonight's radar:

Tonight, migration is weak in the eastern US, except in front of the storm front in the northeast, where there are strong returns that we haven't seen much of yet this spring. There is decent movement up the Great Plains. Take a look at the wind map for the explanation - strong winds from the south carrying migrants up the plains, with strong northwest winds impeding birds behind the storm system in the northeast:

Compare these patterns with several nights ago, when there was strong movement across most of the country. Note generally weak winds in most areas where birds are moving, and strong south winds off the Gulf coast to get them started:

As another influence of weather on migration, I noticed a neat effect here in NY. There are strong migrant returns at the Binghamton, Syracuse, and Albany radar stations where the storms haven't reached yet, but as the rain approaches the birds drop off Binghamton and Albany's radar. Perhaps birding could be good there in the morning?

More migration

Here is an animated version (source) of tonight's migration, which is moving pretty heavily up the central states. For those who weren't sure what represented migration versus weather in the previous images I've posted, this animation should make it abundantly clear - watch the movement pop up in an east-to-west wave as night falls. For a primer on radar birding, see here.

Compare with tonights winds. Strong northward winds all along the golf coast, and weak winds up the central flyway - good movement conditions. (Source).


This is a fun way for me to "watch" birds while I'm up late writing essays for finals...

Crowded Skies Tonight

It's that time of year again - when migrating birds clutter radar screens across the country during night migration. Check out previous posts on the subject for review here. For good radar loops see Rutgers Weather Center.

Before nightfall

11:00PM Eastern Time - the wave reaches the Great Plains

Click to animate

Update: migration spreads farther west

Migration winds down in the morning - 5am Eastern time

8am Eastern time

Field Work Sightings

I've spent the last few days checking the local creeks and my almost 30 artificial nest sites for Northern Rough-winged Swallows (Stelgidopteryx serripennis). I have no activity in any of my nest sites so far, and its starting to get worrying. I still have 1-2 weeks before the swallows should be egg laying, so I've still got my fingers crossed.

One problem I've encountered is wasps. Five out of seven tubes in one stretch of creek were occupied by these guys, which I cleared out to make room for the birds. I only hope the birds weren't turned away by the wasps and will still investigate the tubes for nesting sites. Eric Denemark ID'ed these as Paper Wasps (Polistes). I'm sure it was amusing to watch me clear out the tubes. I would gingerly open the tube until I could access the nest, then jab it with a stick and run like hell. Luckily, these things aren't really aggressive. It was also on the cooler side that day and they may just have been slow.

Check out the eggs

When not engaged in battle with wasps, I did manage to generally enjoy myself hiking along the Ithaca creeks. Heralding the beginning of may, I found my first Mayapples of the year, along with a few other wildflowers:

Mayapple (Podophyllum peltatum)

White Trillium (Trillium grandiflorum)

Wild geranium (Geranium maculatum; thanks for the ID, Amy)

Part of the appeal of these stretches of creek - to both me and the Rough-wings - is the high amount of erosion. Especially impressive are the 100-foot eroded cliffs of Monkey Run, which seem a lot less impressive captured in a photograph:

The low banks where I place my tubes see constant erosion, too. Sometimes you see things like this, where two whole trees have recently collapsed into the creek:

Can you find my wasp-filled tubes?

Belted Kingfishers are abundant along the creeks. I found several burrows this weekend. I measured one to be approximately 40 inches deep - they are not insignificant accomplishments by the Kingfishers!

My attempt to use my cell phone to mirror light down the burrow:

This weekend, I only managed to find one Northern Watersnake (Nerodia sipedon), a young one, but I did actually get a photo of it before it swam into the creek.

My last few sightings are Lepidopteran.

American Lady (Vanessa virginiensis)

Black Swallowtail (Papilio polyxenes)

This was weird. I was walking down the sidewalk of Rt 13 south of Ithaca, when I suddenly had a bunch of caterpillars crawling on me. I looked up, and witnessed many dozens or even hundreds of Tent Caterpillars suspended by silk in the air around a young Red/Black Oak, hung in the wind over Rt. 13. I've seen caterpillars blowing in the wind before, but the magnitude of this event was unreal. Unfortunately their small size made it difficult to photograph, but I tried: