Earth Almanac: March/April 2008

Wrongs to Rights

Cruising underwater for a third of an hour, then punching through the surface to take four to six short breaths, female right whales and their young are migrating from calving grounds off Florida and Georgia to their summer range off New England and Canada’s Maritimes. These are northern right whales, and while two other subspecies (the southern right and north Pacific right) are recognized, all are strikingly similar. Right whales, the first cetaceans to be commercially exploited, got their name because they were slow, easily pursued, and floated when dead—ergo, they were the “right” whale to kill. Their heads, which make up a quarter of their body length, are splotched with callosities—crusty skin growths housing whale lice that graze on dead tissue. Unlike most other whales, rights lack dorsal fins. It is not clear why, after 70 years of protection, the species still flirts with extinction while other whales, such as grays, humpbacks, and sperms, have rebounded. One possible explanation is that right whales are slow and ponderous and therefore especially vulnerable to ship strikes and entanglement in fishing gear.

Dazzling Brilliance

In swamps, bottomland hardwood forests, and brushy stream banks and lakeshores from the Atlantic coast between Florida and New York and as far west as Texas and Kansas, prothonotary warblers are going about the business of breeding. Named for the gold and yellow robes worn by “prothonotaries” (Catholic clerks), they are among our most brilliantly colored wood warblers and one of only two warbler species that nest in cavities (the other being Lucy’s warbler of our southwestern deserts). Male prothonotaries get touchy and territorial in this season, often attacking competitors so ferociously that both combatants fall onto the ground or into water. The male, similar in coloration but moderately brighter than the female, courts her intensely, puffing plumage, spreading wings and tail. Or he will fly close by, serenading her (and being serenaded in return) with soft, rapid tsip notes much different than the more typical loud, sharp tschip call. If the female is responsive, she will alight, twitter, droop and quiver her wings, and raise her rump and tail. When the male finds a potential nest cavity, he shows it off to her by popping in and out.

Smelly Bugs

Throughout most of the United States, box elder bugs, now emerging from hibernation, cause considerable consternation and almost no harm, not even to the box elders and maples on which they may shortly feed both as nymphs and adults. On the Pacific side of the Rockies, you’ll encounter the western box elder bug; on the other side, the virtually indistinguishable eastern box elder bug. Both are about a half-inch long and congregate by the hundreds on windowsills, doorways, and rugs along the south-facing sides of fences, tree trunks, and buildings. They don’t bite or sting, but if you step on them or pick them up, they’ll emit a foul-smelling liquid. Vacuum cleaners are the most efficient means of removing box elder bugs from your house, but empty the bag outside or they’ll crawl out the business end of the machine after you put it away. As you bid them adieu, admire their crimson eyes and striking red-orange stripes on the margins of their black wings and thoraxes.