Plant List Additions

by Carl Strang

Though I have been at Mayslake Forest Preserve for several seasons now, and it has only 90 acres, I continue to find new species of plants. Some of this comes from whittling away at my botanical ignorance, some from needing time to stumble upon those species that are relatively rare there, and some from new species being introduced. The last category has been largely from findings at the restored friary site, which we’ll visit later in the week. The first category has come largely from my diving into the grasses, sedges and rushes. Here’s one that confused me for a time.

Superficially it resembled the bulrushes of genus Scirpus, but despite being fairly common and widespread at Mayslake it matched none of the bulrushes in Swink & Wilhelm’s regional reference.

Eventually I turned to other groups, and with great relief learned it was the common rush, a Juncus. Last week I found a grass that may occur in only one little spot on the preserve, and so it fit into two of the categories.

This is fowl manna grass, a distinctive species growing in a little intermittent trench above the stream.

Another species, common regionally but with few individuals at Mayslake, is the common carrion flower.

This is a thornless member of genus Smilax. Its thorny relatives are called by the colorful name “blasphemy weed” in some parts of the country.

A shrub that was new to me over the winter (when I featured its tiny pods) now is in bloom.

How did I miss this spectacular plant in previous years? My excuse is that the several indigo bushes were buried in other vegetation along the stream, but now have been freed by the restoration team.

I expect my wild plants list for Mayslake to top 300 species before this season is done.

Mayslake Avian Update

by Carl Strang

With the frantic migration season fading away, birds have entered the frantic breeding season. Indeed, some birds already are on their second brood.

I took this photo of a robin fledgling back on May 22, and saw some second nests under incubation last week.

Birds continue to wander, however, and unexpected individuals pop up from time to time.

This coot showed up on May’s Lake one day last week, for example.

There always is something new to learn. On Thursday of last week I saw a female orchard oriole in the north savanna. She seemed to be at home, and so I returned there on Friday, mixing plant survey work with a wish to gain more information on the orioles’ presence.

It didn’t take long to find the male.

He was fairly vocal, but his song and call were more similar to those of the Baltimore oriole than other orchard orioles I have observed in the past (though lacking the loudly whistled “hey batter batter batter” call of that baseball-oriented bird). I had no record of this species at Mayslake last year, but now I wonder if I was hearing this male and labeling him a Baltimore oriole. There always is something new to learn.

Finding Changes

by Carl Strang

My back and leg had healed enough for me to retrieve the amphibian traps from the stream corridor marsh at Mayslake Forest Preserve.

The marsh had dried around the edges, making the approach easier.

As I went, I noticed some changes. The shelf of wood that had supported the ill-fated Canada goose nest collapsed.

Traces of the nest remained, but the eggs were long gone.

I also found two new plants. One was abundant enough that I should have seen it before.

Nodding bur marigold, blooming early for a Bidens, like everything else this year.

There was only one individual of the other plant, so I took photos and a single tiny flower.

It proved to be marsh cress, a member of the mustard family.

There always is something new to be found in preserve monitoring.

May Bird Arrival Phenology

by Carl Strang

May is the last month in which I track migrant bird arrival dates at Mayslake Forest Preserve, as the spring migration is practically concluded. As has been the case this spring, median bird arrival dates have not been nearly as different from previous years as those for first flowers or insect appearances. The 22 species I could compare between 2012 and 2011 were a median 4.5 days later this year, ranging 9 days earlier to 38 days later. The median difference from 2010 was exactly 0, or no difference, with a range of 8 days earlier to 19 days later for 20 species. Finally, 21 species arrived a median 5 days later than in 2009, ranging 10 days earlier to 26 days later.

The rose-breasted grosbeak was fairly typical, the first arriving at Mayslake on May 4 this year, May 2 last year, May 4 in 2010 and April 27 in 2009.

As I mentioned when summarizing data on bird preferences for buckthorn vs. oak woodlands, this year was characterized by a number of migrant species bypassing Mayslake altogether, so there were many for which comparisons could not be made.

May Insect Phenology

by Carl Strang

As was the case with flowering phenology, insect species that first appeared in May did so earlier than in recent years at Mayslake Forest Preserve. The median difference between this year and last was 14.5 days earlier for 18 species, with a range of 86 days earlier to 5 days later. The median difference between 2012 and 2011 was less, at 8 days earlier for 15 species, ranging 21 days earlier to 46 days later. The difference was larger again with respect to 2009, a median of 16.5 days earlier for 14 species, ranging 95 days earlier to 46 days later.

Many of the early species were dragonflies, possibly finishing their development more quickly as waters warmed early this year. The first blue dasher appeared 9 days earlier than last year, 21 days earlier than in 2010, and 14 days earlier than in 2009.

With soil warming and plants growing so much more quickly, it is no surprise that plant-eating insects also were represented among the early species.

I saw the first least skipper on May 22 this year, June 8 last year, June 10 in 2010 and June 2 in 2009.

A third category was migrants, with the monarch butterfly being the iconic species here.

The first monarch arrived on May 4 this year, May 11 last year, May 19 in 2010 and May 26 in 2009.

Though local conditions would not have brought migrants here sooner, much of the U.S. had an early spring which could translate into quicker development of the offspring of those monarch migrants that overwintered in Mexico.

May Flowering Phenology

by Carl Strang

In May, plants at Mayslake Forest Preserve continued to bloom around 2 weeks early, as compared to recent years. Here are the specifics: the median difference between 2012 and 2011 for species that first bloomed this May was 16 days earlier this year, with a range of 86 days earlier to 3 days later among 64 species. The median difference vs. 2010 was 11 days earlier in 2012, ranging 48 days earlier to 12 days later in 41 species. The median difference vs. 2009 was 18 days earlier, ranging 42 days earlier to 7 days later for 43 species.

Foxglove beard tongue was reasonably representative, blooming first on 21 May this year, 17 days earlier than last year, 5 days earlier than in 2010, and 15 days earlier than in 2009.

The difference from previous years diminishes somewhat from month to month, but I don’t expect things to even out before July or August.

Birds, Buckthorn and Oaks Final

by Carl Strang

As I mentioned in my previous post on this subject, the songbird migration was nearly done by mid-May. In fact I have only 3 observations to add to the ones from the early part of the season, two in the oaks and one in the buckthorn-dominated woodland. That mildly reinforces my earlier conclusion, that the only reason buckthorn woodlands appeal to birds early in the season in our area is that oaks, which dominate most of our woodlands, leaf out late. In this year when the oaks were in leaf throughout the migration season, songbird migrants nearly abandoned the insect-depauperate buckthorn at Mayslake Forest Preserve and spent their time in the oak woodlands.

South savanna at Mayslake, showing oaks well leafed.

So far all the analysis has been of the total species counts of neotropical migrants that do not nest at Mayslake. However, some of those species are brush specialists that might be expected to prefer the buckthorn over the more open oak woodlands regardless of what is happening in the canopy.

The Tennessee warbler is an example of a canopy species, on the other hand, which will not want to spend a lot of time foraging down in the buckthorn, though they might want to have it handy for resting and as a refuge from predators.

When I look at the two years’ data, sorting out brush from non-brush birds, the most curious observation is that hardly any brush-loving birds stopped by Mayslake this year. Only two birds out of the total sample of 30 were of brush species. Last year, 38 of 166 were brush birds. Looking at 2011, then, both brush and non-brush birds preferred the buckthorn woodland early in the season, though the preference was stronger for the brush species. Late last year, after the oaks were leafing out, non-brush species preferred oaks while the brush birds did not show a strong preference for either woodland type.

All of these data, coming as they do from one site over a short period of time, amount to a pilot study at best. Nevertheless, they support the notion that the apparent preference of migrant songbirds for woodlands dominated by invasive shrubs is an illusion. Birds avoid the buckthorn and prefer restored native woodlands when the latter are in leaf, capable of providing both food and essential shelter.

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