Thursday, March 21, 2024

Spring Botany Blast! New River Gorge, West Virginia, April 11 - 14

The inaugural Spring Botany Blast! takes place this April 11 - 14 in and around the incredible New River Gorge in West Virginia. This region is a plant aficionado's paradise. A diversity of habitats, mostly wooded, in stunning mountain environs, harbor scores of wildflower species, often in great profusion. We'll be based at Hawk's Nest State Park, which is convenient to all of the special hotspots that we'll be visiting.

Spring Botany Blast! was started as an offshoot of the New River Birding & Nature Festival, in which I have participated as a guide and speaker for about 20 years. So, I feel I know the area pretty well, but my co-leaders Rosanna Springston, Jodi French-Burr, and Mitchell Dech know the region even better, as locals, and are also intimately familiar with the flora (and fauna).

CLICK HERE for more details, and registration information. It'll be a whirlwind weekend filled with great botanizing amid some of the showiest scenery in the eastern U.S. Following are some shots of some of the wildflowers that we'll see, but this is just a tiny snippet of what to expect. Photo ops will abound, and I'm glad to work with anyone on improving their tactics for making plant imagery.

There aren't many spaces left, so I'd suggest acting soon. Hope to see you there!

Blue-eyed Mary (Collinsia verna)

Carolina Spring-beauty (Claytonia caroliniana)

Mountain Magnolia (Magnolia fraseri)

Large-flowered Bellwort (Uvularia grandiflora)

Long-spurred Violet (Viola rostrata), rare white-flowered form

Red Trillium (Trillium erectum)

Fire-pink (Silene virginica)

Sunday, March 17, 2024

Eastern Red Bats, moths, and leaf litter

Hi all, and thanks as always for reading! Sorry for the long (for me) lapse in posts. Things have been a bit busy of late, and it's been tough to carve time out to sit down and craft a new piece. But here we are, and away we go.

An Eastern Red Bat (Lasiurus borealis) nestles among the leaves of an American Beech (Fagus grandifolia). This species is the consummate tree bat, and its range mirrors that of the great eastern deciduous forest, which spans the eastern half of the U.S., stretching from the Gulf Coast into southern Canada.

Shauna Weyrauch and I have had some interesting field excursions of late, two of which involved inspecting relatively small woodlands in central Ohio. In one, we found the bat pictured above, and in the other, we found not one, but two bats ensconced in a beech. These experiences got me thinking a bit deeper about the tiny bats (as little as 10-12 grams! About the same weight as a Song Sparrow!).

A young American Beech in a Franklin County, Ohio woodland. Beech typically retains many leaves throughout the winter, and they are still on the tree come spring. Also note the rich leaf litter on the forest floor. By the way, the Red Bat pictured above is in this photo, towards the far-left side of the leafy limb that sticks out the furthest. It looks like a little dark blob.

We move in a bit closer, and now you'll probably see the wee mammal. After one gets the search image, it isn't too tough to spot roosting Red Bats - if you're giving the trees the once-over. Beech seems to be the best host, at least that's the plant that I've found most of them in. They likely hide among long-persistent oak leaves as well and are known to roost on the ground buried in leaf litter. I once saw one making aerial hunting forays during the day and the bat would return to hide under exfoliating bark high in a hickory between runs. But beech may be the easiest to find them in, and it's always worth giving trees like the one above a good look.

A Common Oak Moth (Phoberia atomaris) rests in leaf litter. As soon as we entered this woods, we began flushing moths from the litter. As it was pretty early - March 14 - I was keen to know what they were. Not many moths are yet out. It didn't take too long to get an answer, and we went on to see many of these oak moths. It seemed that every we flushed and saw well was this species, and that was quite a few.

Moths that emerge this early - this species overwinters as pupa in leaf litter - may be tied to early spring sap flow in trees. There are few if any floriferous nectar sources yet available, but sap provides a ready source of sugar for energy and a number of moth species visit oozing sap.

Face on with an Eastern Red Bat. Moths are the number one prey group for eastern bats, and relatively hefty oak moths as in the previous photo would make quite a meal for the little mammals.

I was especially interested in the potential moth-bat link as I've never encountered Eastern Red Bats in March and think of them as largely an April/May phenomenon. A quick glance at iNaturalist also shows many more April than March records at this latitude.

Red Bats are migratory, and it's thought that the majority of bats at northerly latitudes, including Ohio, migrate to southeastern states for the winter, and return in spring. Perhaps the earliest returnees are synced to arrive when very early spring sap-feeding moths emerge? These March sap-feeders are quite hardy and can fly in low temperatures. I once saw scores of Morrison's Sallow moths (Eupsilia morrisonii) flying about a northern Ohio woodlot on a March night when temperatures were in the mid-30's.

Another possibility is that the bats that we are encountering in early/mid-March are ones that overwintered. My hunch, though, is that they are migrants moving north with the first warm days, as the weather was in the 60's and even low 70's F for a few days preceding our observations.

An Eastern Red Bat tucked into senescent beech leaves.

A great many moths (bat food) are highly dependent upon leaf litter. As noted, the Common Oak Moth pupates in leaf litter, and habitually hides in it during the day. When flushed, the moths quickly return to the litter and often scuttle under the leaves. The aforementioned Morrison's Sallow overwinters as adults, but probably also spends its days hiding among leaf litter, along with numerous other species. There is even a subfamily of moths known as litter moths, as the caterpillars feed on dead leaves.

Leaf litter spawns lots of bat food in the form of moths. Fortunately, we don't generally have to worry about the leaf-blower crowd taking to the forest. But those dastardly devices do enough damage in areas where leaves should remain. Even suburban/urban gardens can produce plenty of moths if leaves remain in garden beds and other places where there is no reason to blow them away.

It remains to be seen how the continuing onslaught of nonnative invasive earthworms will impact moth production. These worms can transform an ordinarily leafy forest floor to bare dirt in short order. I've seen the effects, and it is dramatic. Presumably, such litter decimation has an adverse impact on litter moth production and by extension bats. If you aren't familiar with the worm issue, CLICK HERE.

Be sure and scope out any leafy beech you might encounter this spring. Look for little dark reddish blobs among the senescent brown beech leaves. The odds of finding one probably increase if a stream is nearby, as bats often hunt over stream corridors at night. Search enough beech and sooner or later you'll turn one up. It's a magical experience.

Monday, March 4, 2024

Bewick's Swan: An Ohio First


A quintet of Tundra Swans (Cygnus columbianus) prepares for landing.

I attended the annual Ohio Bluebird Society's annual meeting last Saturday, March 2, to speak about moths. Little known fact: The majority of the Eastern Bluebird's non-winter diet is moth caterpillars. Shauna and I had a great time, met lots of people, and I saw scads of friends that I haven't seen in a while. The Society is quite active and about 140 people were in attendance.

Afterwards, Shauna and I took the long way home, in order to visit Killbuck Marsh - one of the largest interior wetland complexes in Ohio. Killbuck lures scads of migratory waterfowl in spring, including large flocks of Tundra Swans (Cygnus columbianus). On February 23, Josh Yoder located a "Bewick's" Swan in a large flock of Tundra Swans, and I'd wanted to get up there to see it ever since. That bird was our primary target on this trip, and it wasn't hard to find, especially as many birders were on the scene.

The Bewick's Swan is now (mostly) considered to be a subspecies of the Tundra Swan (Cygnus columbianus bewickii). However, it has been considered a separate species in the past, and the American Ornithological Union didn't lump it into the Tundra Swan until 1983. While most authorities dealing with avian nomenclature and taxonomy consider it to be a subspecies at present, Avibase separates the two.

A pair of Tundra Swans drops in, landing gear extended. Don't expect National Geo-caliber imagery in this post. The flock of Tundra Swans that our target fraternized with was a LONG way across the marsh. Maybe 200 yards or so, so it took some photographic oomph to even get the documentary shots that I did. I used my Canon 800mm coupled with a 1.4x extender (1120mm) and that's generally not the ticket for sharp vibrant shots on a heavily overcast day. Nonetheless, the rig did allow me to capture diagnostic details of the bird in question.

As always, click the photo to enlarge

As a point of comparison for the bird to follow, here's the nominate subspecies of Tundra Swan - the subspecies that occupies North America and occurs in Ohio during migratory periods. That's an adult on the left, with a juvenile facing away from the camera. Note the classic small yellow teardrop on the bill, in front of the eye. While some individuals can have all black bills, a little fleck of yellow as on this bird is pretty typical.

One of these swans is not like the other. Specifically, the bird second from right. Even from afar, the big yellow blotch on the bill stands out. A typical Tundra Swan shouldn't (couldn't?) ever show that much yellow.

Here's the range map of the Tundra Swan, courtesy of the Cornell Lab of Ornithology Birds of the World website (I'm a longtime subscriber, and anyone with a serious interest in birds should consider a subscription, found HERE).

For the most part, all of the birds represented in America are Tundra Swans, and those in Eurasia are Bewick's Swans. A rub: The nominate subspecies of Tundra Swan (the North American birds) also breed in eastern Siberia, and hybridization between the two subspecies occurs there.

Here's the best that I could do to photographically capture the Ohio Bewick's Swan. While that big splotch of yellow exceeds anything that could, or at least should, be present on a Tundra Swan, classic Bewick's Swans can show even more yellow. On some/many/most Bewick's, that yellow forms an even larger blotch, and can extend across the top of the bill to connect the two side patches. Whether the yellow marks increase in size with age, I do not know.

Here is a germane quote from the Bird's of the World Tundra Swan account:

Birds appearing identical to the Palearctic form (C. c. bewickii) reported occasionally in w. North America (Alaska, Alberta, Saskatchewan, Oregon, and California). Some of these are likely true bewickii, but others may be bewickii x columbianus intergrades from e. Siberia, or even variants of columbianus with excess yellow on the bill. The occasional bewickii reported farther east in North America may represent escapees from captivity.

To address the latter point about escapees: While many species of waterfowl are kept - sometimes fairly commonly - in captivity, and occasionally escape, I don't think that's the case here. A search, less than comprehensive, admittedly, for Bewick's Swans for sale revealed nearly no sellers, and I've not personally heard of this subspecies being peddled by waterfowlers, at least in this part of the world. Also, the appearance of the Ohio bird syncs perfectly with the major northward push of Tundra Swans, and it is fraternizing with them. Presumably a wayward Bewick's Swan, prone to vagrancy, would also wander at this time of year. And more records have occurred in the east since that quoted paragraph above was written. eBird records about a dozen records to date from the eastern U.S. and Canada.

The bigger question involves hybridization between the subspecies, and definitively answering that is well beyond my paygrade. While I've seen many thousands of the nominate Tundra Swan subspecies, I've got next to no experience with Bewick's Swan. I think it would be very helpful to get images of this bird to someone who sees lots of Bewick's Swans and understands their variability, and especially the appearance of hybrids between the subspecies.

NOTE: It is always helpful to remember that "species" are merely a human compartmentalization scheme. All species are in a constant state of evolution and where one draws the line of separation between two very similar "species" or especially "subspecies" is almost always somewhat arbitrary.

Any way one slices this swan, it was a great find by Josh Yoder, and the bird offers interesting food for thought, in addition to its undeniable curb appeal. It is an apparent first state record for Ohio, and one of very few reports anywhere in eastern North America.