Thursday, July 14, 2011

Royal catchfly, a beautifully sticky bit of business

Before we get on with the business at hand - royal catchfly - I want to share two beautiful images of one of our rarer birds, courtesy of Dane Adams. Emil Bacik discovered not one, but two Piping Plovers at Lorain Harbor on Lake Erie yesterday. They are still there as of today, and Dane made the scene.

Photo: Dane Adams

The Great Lakes population of Piping Plover is imperiled, to say the least. Listed as federally endangered, this charismatic species had plummeted to about 12 breeding pairs by 1983. Protection of their beach nesting habitats has allowed for some growth in the population, and current estimates place the number of pairs at less than 70. There may have been as many as 700 breeding pairs along the Great Lakes prior to European settlement. Some of them bred on Ohio's Lake Erie beaches, but the last nesting dates to 1942. We only get the occasional migrant now, such as these birds in Dane's photos.

Photo: Dane Adams

You may have noticed that these birds' legs are heavily ornamented with bands. The colors and combinations indicate where they originated, and when. I suspect that someone is running down this information, and if I learn the back story on these pipers, I'll pass it along.

Anyway, in perhaps the world's first blog post to combine Piping Plovers and royal catchfly, we switch gears and jump into Bigelow Cemetery, a remnant of the once vast Darby Plains tallgrass prairie. Bigelow is a state nature preserve not far west of Columbus, Ohio, and is a must-see for anyone interested in prairies.

I was there recently, and the star of the prairie show, royal catchfly, Silene regia, was nearing peak bloom. This is a big plant; its magnificent spikes can shoot up four feet or more.

If you are interested in planting native species, especially in the context of a prairie garden, royal catchfly is a must-have. Several vendors, most notably the Ohio Prairie Nursery, had them for sale at last weekend's Midwest Native Plant Conference and sold lots. By the way, that conference went smashingly and was a ball, and I'll be sharing some photos from the event later.

The brilliant red flowers are star-shaped and sport a long corolla tube. Not surprisingly, they never fail to attract Ruby-throated Hummingbirds.

Here's why royal catchfly - and many of its brethren in the genus Silene - has the "catch fly" in its name. In this tight shot of the upper stem, we see gnatlike bugs and even a few beetles that became ensnared by the plant's viscous glanduar hairs, got stuck, and perished. Press a calyx - the tubular lower portion of the flower - between your fingers sometime. You'll instantly notice the Elmer's Glue-like quality of the plant.

This sort of thing interests me. It stands to reason that these sticky hairs that arm the upper portions of the plant are a defense against insects making their way up the plant from the ground. The plant is, in essence, trying to select for airborn pollinators such as the aforementioned hummingbirds, as those pollinators are probably a more efficient way to disperse pollen. But, when hairs such as these on the catchfly evolve to such a stickiness that they kill insects, is this a step towards evolving carnivory? In fact, I wonder if anyone has looked at royal catchfly to see if the plant already is capable of assimilating proteins and other useful goodies from the bugs that die on its stems.

Not all small insects perish on the gluey catchfly stems. I noticed that many of the plants had small colonies of of tiny blackish lentil-shaped aphids, which seemed to be able to move around with ease and are presumably completely specialized to feed on royal catchfly. All of these aphid colonies were tended by ants -two of them can be seen in this photo - and they also had no problem negotiating the sticky stems. Ants often associate with aphids, feeding on nutritious "honeydew" secreted by the tiny insects. In return, the brutish and warlike ants guard the helpless aphids against predators.


LauraHinNJ said...

Piping Plovers aren't banded here, Jim, as far as I know... I'd wondered about that and asked the NJFandW Biologist that's studying our site... she said something about a problem with the bands/the birds' feeding habits... heard of that? It doesn't feel "right" to me that birds so closely monitored here not be banded... ideas?

Jim McCormac said...

Not sure why they don't band there, Laura - I think every one that breeds in the Great Lakes is heavily ornamented with various flags and tags. It's a miracle they can fly :-)

Anonymous said...

The paper you should check out is Spomer, G.G. (1999) Evidence of protocarnivorous capabilities in Geranium viscosissimum and Potentilla arguta and other sticky plants. Int. J. Plant Sci. 160(1): 98 - 101. You should be able to access JSTOR from a library to get access. He looks at protocarnivory in other Caryophyllaceae.
I'll be linking to your photos for a little presentation on possible protocarnivory in Silene. Great shots!