Friday, December 13, 2013

Roadside Pollinator Gardens and Traffic


Mountain laurel. © Beatriz Moisset
Pollinator gardens are blooming along many highways. Perhaps the idea originated with Lady Bird Johnson and her beautification program. But it goes well beyond that. Planting wildflowers along highways has many advantages besides the esthetic ones. With the growing loss of pollinator habitat, it is a blessing to use the wasteland of roadsides as wildflower gardens to take care of the needs of pollinators.

Butterflies and bumble bees are more abundant where wildflowers bloom than in areas where grasses are dominant and where mowing and pesticide treatments are routine according to many reports. The possible downside is that larger numbers of dead butterflies, and perhaps bumble bees are found along highways with abundant wildflowers. How serious is the problem? Do the benefits outweigh the damages?

Skipper on asters. © Beatriz Moisset
It isn't easy to assess all the aspects of the situation. But the weight of opinion is that the deaths by vehicles are not much higher than those by natural causes. The increase in food supplies and shelter for the pollinators benefits them and contribute to larger populations. So, those who study the matter feel that it is worth to continue creating habitat for pollinators along highways.

Other advantages of such roadside pollinator gardens are a reduction in mowing frequency once the gardens are established and a reduction in pesticide use. Did I mention that the view is also more pleasant to the eye? Perhaps, this improves the mood of the drivers and brings down accident frequency.

Milkweeds. © Beatriz Moisset

References

Pollinators and Roadsides. Xerces Society. 
Manage your Roadsides for Bees & Butterflies. 
Use of Roadside Prairie Plantings by Native Bees. Iowa State University. 
Roadsides as Habitat for Pollinators: Management to Support Bees and Butterflies. Jennifer L. Hopwood.
A Sticky Situation for Pollinators. Minnesota Conservation.

Saturday, December 7, 2013

Globetrotting Skippers


Fiery skipper (Hylephila phyleus). © Beatriz Moisset
 You probably thought I was running out of migratory butterflies after my last two posts. Not quite, there are more. But now I want to turn to skippers and talk about two species that also deserve the name of globetrotters.

Skippers are related to butterflies and often they are called by that name. The clearest difference between the two is that the end of a skipper's antennae ends in a hook, while that of a butterfly ends in a knob. Most are not as colorful as butterflies, they skip along when flying, hence their name.

Butterflies, skippers and moths belong to the order Lepidoptera, which literally means "scaly wings." You can tell them apart from all other insects by this feature. Perhaps, in a future post I will deal with migratory moths. Yes, there are some of those, too. In fact, a few perform amazing trekking feats.

As I mentioned, we know very little about the itineraries and distances covered by migratory butterflies, other than monarchs. We know even less about skippers. The only fact we are certain of about the ones I want to discuss today –the fiery skipper and the long-tailed skipper– is that they travel long distances, not just locally.

Fiery skipper (Hylephila phyleus) is one of the so called grass skippers because its caterpillar feeds on grasses. It has a bright orange color. It lives in temperate and tropical areas and can be found from North America to Brazil and Argentina. Let me clarify that this is its geographic distribution and it doesn't mean that it travels that far. The ones that live in South America are different populations. However, as I said before, it travels north in the spring from the southern states to northern areas. It is thought that many of those migrants don't make it back. Instead, they freeze and die when the weather gets cold.

Long-tailed skipper (Urbanus proteus). © Sean McCann. Bugguide
 The long-tailed skipper (Urbanus proteus) is unusual in two respects, each hind wing has a long projection that gives it its name, and its caterpillar feeds on members of the pea family. This latter characteristic doesn't endear it to farmers. The caterpillar is often called the bean leaf roller because it finds shelter by wrapping itself inside a leaf of this plant. It is just as widespread as the fiery skipper. Once again, it is not known if the ones that travel north or their progeny ever make it back to the South.

Years ago, it was thought that some of the travelers mentioned in previous articles failed to return south when the weather deteriorated perishing at the end of the season. Later on, additional observations showed that painted ladies, red admirals and a few others, do indeed return south in the fall.  I hope that, as we find out more about these two species, we learn that they too are capable of escaping the winter weather by migrating south in the fall.

Butterflies and Moths of North America (Range)
Long-tailed Skipper or Bean Leafroller (Distribution)
Migration: The Biology of Life on the Move (Urbanus proteus migration)

Globetrotting Butterflies
More Globetrotting Butterflies

Monday, December 2, 2013

More globetrotting butterflies


Monarch butterfly, the most famous traveler. © Beatriz Moisset
In my last post I discussed two butterflies, the red admiral and the painted lady, that rival the monarch in their annual journeys. If you found this information surprising, you would be even more surprised to learn that there are several other butterfly globetrotters. Other insects capable of long range migrations are several species of dragonflies. There may be many others.

Let us look at a few more migratory butterflies.

Cloudless sulphur. © Lynette Schimming. Bugguide.net
Sulphurs are butterflies that range in color from lemony yellow to orange. The name refers to their color. One among them, the cloudless sulphur (Phoebis sennae), travels from Canada to Texas, Florida, and Mexico in the fall. It also lives in South America, as far south as Argentina. We don't know much about the migration of the cloudless sulphur, other than when going south in the fall, they move steadily and purposely, hardly stopping to eat. We know even less about the ones that live in South America, whether they travel much and whether they mix with the North American populations.

Common buckeye. © Beatriz Moisset
Another lovely vagabond is the common buckeye (Junonia coenia), so called for the distinctive spots on its wings. Not content with one pair of eyespots, it has three. Not visible when the wings are folded, they make quite a display when it decides to spread them. It must be a scary sight to a hungry bird, which may induce it to leave the morsel alone.

Common Buckeye. View of the underside. © Beatriz Moisset
When the monarch butterfly shows in large numbers in Cape May, NJ, every October and November, so does the common buckeye. I am just as happy to see one as the other. It lives year round in the southern states, as well as in Central America and Colombia. Apparently, some don't travel much; others get the urge to go north, as far as Canada. Their descendants head south in the fall. Once again, we don't know much more about its movements.


A gaggle of buckeyes takes a rest on their way south
  © Beatriz Moisset
It is curious to me that only one globetrotter, the monarch butterfly, has caught the public imagination, leading to numerous observations. Nowadays, we know quite a bit about its complicated trips north and south. I am just as eager to learn about other tiny organisms' urge to cover large distances that seem to exceed their capabilities. I hope this awakens your appetite for more information on all these adventurous little souls.