Migrant Bird April Arrivals

by Carl Strang

In contrast to the much earlier flowering dates and insect appearances that I recounted in the previous two posts, April’s birds arrived on dates much closer to those of earlier years. Median dates were 4 days earlier in 2012 than in 2009, 0.5 day earlier than in 2010, and 2 days earlier than in 2011.

One of the April birds that had traveled the farthest was the chimney swift. Following their instinctive schedule, the first of these appeared at Mayslake Forest Preserve on April 19, not much different from 2009’s date of April 24, April 21 in 2010 and April 25 last year.

The medians represent samples of 13, 14 and 13 species in the three comparisons, respectively. The largest range was the comparison to 2009, at 21 days earlier to 26 days later.

Lesser scaup first stopped by May’s Lake on April 5, distinctly later than the dates of 10 March, 16 March and 31 March in 2009-2011, respectively.

The contrast with flower and insect phenology is stark, and indicates how responsive those two groups are to local conditions. These birds wintered well to the south, have no idea of local conditions, and simply follow the dictates of their biological clocks and instincts. I expect to see little difference in May as well.

Migrants Trickle In

by Carl Strang

It’s time to play catch up on the migration season. We have been seeing mainly birds that spend the winter in the southern U.S., but the last week of April usually brings the first wave of tropical migrants, so I want to clear the deck of accumulated migrant photos from Mayslake Forest Preserve.

Every spring a few lesser scaup stop by the preserve’s lakes on their way north.

Last week a ruddy duck spent a day on May’s Lake.

This was a new species for the preserve bird list.

Waves of northern flickers have been passing through.

This has been more a migrant than a nesting species at Mayslake.

Brown-headed cowbirds have been around for a few weeks, now.

Some of these males have been setting up group territories and courting females.

Ospreys have stopped by a couple times, but we haven’t yet seen a prolonged stay by one as has happened the past two years.

Nevertheless, a glimpse of this species always is welcome.

 Swallows have been coming through in large numbers.

In addition to tree swallows, many northern rough-legged and barn swallows have been foraging over May’s Lake.

 While the golden-crowned kinglets mainly have shifted north of us, ruby-crowneds still are coming through.

These tiny birds delight with their active movement and their bubbling, forceful songs.

 As of last week, most early migrants have made their first appearances earlier than in 2009 and 2010 despite the cold weather we have been experiencing. While weather can influence them, they are driven mainly by photoperiod and will push north as long as they are finding food.

Spring Comes to Mayslake

by Carl Strang

Yesterday I looked back at late winter on Mayslake Forest Preserve. Today I want to share some early signs of spring. There still was a patch of ice on May’s Lake when the first migrant ducks, some lesser scaup, stopped by.

Flocks of sandhill cranes have been passing over on the nicer days.

We also have seen the first flowers of the season already, on silver maples.

Garlic mustard seedlings have germinated.

Soon I’ll resume my experiments on controlling this problem species. Other recent spring events have been chorus frogs singing, the first active chipmunks, red-bellied woodpeckers calling near where they nested last year, and the appearance of insects that overwintered as adults, including a box elder bug and a mourning cloak butterfly.

The Ducks Stop Here

by Carl Strang

 

This spring I have been impressed by the variety of migrant ducks stopping at Mayslake Forest Preserve. They haven’t come in large numbers, and haven’t stayed long, but the diversity has been interesting. So far I have seen (in addition to local mallards) shovelers, wood ducks, pintails, lesser scaup, hooded mergansers, and this bufflehead pair.

 

buffleheads-b

 

In addition, last fall a ring-necked duck spent a day. The brief stays and low numbers suggest that the habitat quality may be limited in some way. On the other hand, two pied-billed grebes have stayed on one of the lakes for several days, now, so there is food at least for carnivorous divers. The migration has just begun, and I look forward to discovering which species give Mayslake a try as their daytime stopover site.

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