Eagle Marsh Bioblitz

by Carl Strang

Each year the Indiana Academy of Sciences selects a site within that state for a bioblitz. This past weekend’s was my third, and it always is a great way to kick off the field season. The location this year was Eagle Marsh, on the western fringe of Fort Wayne.

A large open barn in the center of the site made for a good headquarters.

A large open barn in the center of the site made for a good headquarters.

Support for the visiting scientists and other volunteers was excellent. Here, the morning’s adventures are shared over box lunches on Saturday.

Support for the visiting scientists and other volunteers was excellent. Here, the morning’s adventures are shared over box lunches on Saturday.

The objective of a bioblitz is to find as many species of organisms as possible in a brief period, usually 24 hours. Scientists who specialize in different taxa lead teams that explore the site. Eagle Marsh is dominated by wetlands, as the name implies. In fact it sits on the boundary between two watersheds, the Great Lakes to the north, and the Mississippi River drainage to the south.

This fence is intended to block Asian carp from reaching the Great Lakes when the rivers flood. It soon will be replaced by a more reliable berm.

This fence is intended to block Asian carp from reaching the Great Lakes when the rivers flood. It soon will be replaced by a more reliable berm.

The site largely is a restoration project begun in 2005, though some teams found surprising diversity in parts of the preserve. My singing insects team was limited by the early date. We found a grand total of 3 species.

This Roesel’s katydid nymph was one of a small cluster we found on an elevated bank.

This Roesel’s katydid nymph was one of a small cluster we found on an elevated bank.

This bioblitz invited members of the public to assist those scientists open to such participation. I was delighted to have a team, for a change, and we enjoyed all the organisms we were finding.

Northern leopard frogs were abundant, a sign of how rapidly the wetland is improving in quality.

Northern leopard frogs were abundant, a sign of how rapidly the wetland is improving in quality.

Peck’s skipper was one of a number of butterfly species we observed.

Peck’s skipper was one of a number of butterfly species we observed.

Jeff Holland’s Purdue University entomology team always provides a highlight with their beetle-drawing lights.

1000 watts of power.

1000 watts of power.

Helpers collect some of the insects that fall to the sheets below.

Helpers collect some of the insects that fall to the sheets below.

Here is what they were seeing.

Here is what they were seeing.

Congratulations to Betsy Yankowiak and the Little River Wetlands Project team for a job well done.

Betsy presented an overview of the area’s geology for interested participants.

Betsy presented an overview of the area’s geology for interested participants.

The American Snout, and More

by Carl Strang

One of my favorite animal names is “American snout.” It calls forth the image of some disembodied nose floating in space. In fact it’s a reference to a butterfly with a long forward extension of its head.

This butterfly was the first of its kind I have observed at Mayslake Forest Preserve. It is more common south of us. In references you may find its species name as carinenta or bachmanii; the genus is Libytheana, and there is only one North American species.

Another preserve first was this brightly colored beetle.

The milkweed leaf beetle, like so many consumers of milkweed, has bright orange colors. These warn potential predators of the possibility of poisons the insect may have sequestered from its diet.

I saw a couple bluets that had the relatively large size and the color pattern of familiar bluets.

The males had this violet coloration, though; my guess is that they had recently emerged as adults and would be changing colors soon.

I have been seeing more Virginia ctenucha moths than usual this year, at Mayslake and elsewhere.

That’s the way it is with some insects, having occasional years with higher numbers.

Of course, a major goal of all these adult insects is to find a mate and produce eggs.

For this pair of least skippers, it’s so far, so good.

On Friday I finally saw the first Peck’s skipper of the year.

The pattern of light spots beneath the hindwing is distinctive for this species.

It’s been a good year for insects, so far.

More Insects Emerge

by Carl Strang

Phenology, the timing of natural history events, is an easy area of study that adults or schoolchildren can pursue. I have been sharing my phenology observations at Mayslake Forest Preserve for first flowers, first fruits, and spring arrivals of migrant birds. Today I would like to look at results comparing 2009 and 2010 spring first sighting dates of insects. Insects are small and easy to overlook. Their numbers can vary a lot between years. Consequently I am not going to place too much weight on small differences between years for individual species. A case in point is the hobomok skipper.

I have seen few of these at Mayslake. Nevertheless, last year’s first date of 5 June is very close to this year’s June 9. Similarly, the first prince baskettail dragonfly appeared on June 1 last year, June 10 this year.

They seldom land, so I’m resorting to a UFO photo here. The difference in dates for Peck’s skipper is large enough to suggest a brood difference. I saw this one on May 25 this year.

The first date last year was August 24. This represents last year’s second generation, and I did not see a first generation representative. I don’t see many of these butterflies, so this is not a surprising result. I also haven’t seen many lyre-tipped spreadwings

Thus I am not willing to put much emphasis on the between year difference in first sightings of 13 July 2009 vs. 10 June 2010 for this damselfly.

So much for individual species. I was interested in looking for patterns among seasonal groups of species. In March this year I had only 2 species to compare to 2009, with a median difference of 5 days earlier than last year. April numbers were 9 species, median 17 days earlier than 2009. The 12 May species had a similar 16.5 days earlier median. To date in June, 9 species are a median 4 days earlier. These results suggest that the warmer spring this year is producing emergence patterns in insects that are similar both in direction and amount to those of first flower dates in plants.

Mayslake Lepidoptera Update

by Carl Strang

As we move into autumn, the lateness of the season calls for us to enjoy the more ephemeral beauties of nature while we still have them. Monarch butterflies have completed their local mating and egg-laying, and have begun the migration south toward Mexico.

Monarchs mating b

Earlier in the season at Mayslake Forest Preserve I found this larva of the moth Cycnia tenera on its usual food plant, dogbane.

Cycnia tenera b

Tiger swallowtails are one of our more spectacular butterflies.

Tiger swallowtail 1b

They will overwinter in the pupal form. Late season species include the summer azure.

Summer azure b

Larvae of this little butterfly feed on flowers in the composite (sunflower) family; I have seen them laying eggs on wingstem at Fullersburg . Another common late summer species is Peck’s skipper.

Peck's skipper b

There probably will be little more to report on this group at Mayslake until next year.

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