Were you able to identify from their illustrations all six things found at Hilton Pond Center? And did you figure out their "Connections" without coming directly to this page? (Or would you rather go back and try a little harder with A Quiz on "Connections" ?)

If you live in the South, chances are you did better on the quiz than folks from north of the Mason-Dixon Line or the western U.S. Nonetheless, even non-southerners may recognize the blossom of the Southern Catalpa tree, Catalpa bignonioides (right), because it is similar to that of the Northern Catalpa, C. speciosa. Both species have been planted extensively outside their original ranges, and both produce large heart-shaped leaves, have fragrant and showy late spring flowers, and bear fruit that resemble long green cigars.

But the Southern Catalpa is especially prone to attack by larvae of the Catalpa Sphinx Moth, Ceratomia catalpae (top)--whose caterpillar is treated with mystical reverence and respect by southern anglers who believe it is a bait irresistible to fish they refer to almost as reverentially as "brim." Elsewhere, folks call these several fish species "bream" and "panfish," or more correctly "sunfish"--as in the Green Sunfish, Lepomis cyanellus (below left).

In another display of regional pride and colloquialism, many fishermen in North and South Carolina use the names "Catawba worm" and "Catawba tree"-- misnomers that arose because the Catawba River flows through both states. Regardless of exactly what they call the Catalpa tree and Catalpa Sphinx Moth caterpillar, fishermen have learned to cut the "worm" in half, turn it inside out, and slide it onto a hook. Apparently the caterpillar's powerful scent is highly attractive to fish--particularly panfish and catfish--even when nothing else seems to work. As a result, it's quite common in the Carolinas to find a Southern Catalpa tree planted near a favorite fishing hole, which we suppose is why there's one growing on the banks of Hilton Pond. Created in the early 1950s to water livestock and stop erosion, the pond was stocked with brim and bass and fished heavily for three decades, but today we let our finny friends swim free--at least until they satisfy the hunger of local River Otters or a passing Osprey.

Leaves from Catalpa trees are the only kind munched upon by larvae of the Catalpa Sphinx Moth, which has a spindle-shaped body and long, narrow wings than span about three inches (photo at right © Paul Opler). Its forewings and body are gray with irregular markings, while the hindwings are more brownish. Adults appear in March or April and mate, with fertile females depositing eggs in a mass of 100 to 1,000 eggs on the undersides of Catalpa leaves. Eggs hatch in 5-7 days, after which young larvae feed together voraciously, turning leaves to skeletons and molting five times within a month. Older larvae grow to three inches in length and dine alone, often devouring even the veins of leaves. In the process, all these voracious caterpillars produce huge quantities of metabolic waste in the form of "frass" (photo above left)--a politically correct name for dry pellets of indigestible material. These carpet the forest floor beneath an active colony and likely return a little nutrient material back to the Catalpa tree.

The typical Catalpa Sphinx Moth caterpillar has a black head, a black and yellow stripe down each side, and a slightly curved black "horn" on the posterior (right) that may serve to deter potential predators. Most individuals are dark above and light yellow beneath, but there's also a pale phase that is yellow overall with irregular black markings on its back. In either case, the larvae are smooth-skinned and completely hairless.

When it has eaten its fill and reached full size, the Catalpa Sphinx Moth caterpillar crawls to the ground and forms an inch-long reddish-brown pupa in shallow soil, emerging as an adult about two weeks later. This cycle can occur as many as three or four times a season, with the autumn generation overwintering as pupae in the humus beneath Catalpa trees.

For some reason still unknown to science, some Southern Catalpas are completely defoliated by Catalpa Sphinx Moth caterpillars, while others go untouched. The big tree at Hilton Pond Center is one that loses all its leaves during an outbreak--something that could lead to the tree's death if it happened annually or more than once in the same season. Fortunately for Catalpa trees, Catalpa Sphinx Moths are cyclic; some years there seem to be millions, but in others few caterpillars can be found. This apparently is due, at least in part, to population cycles of a small wasp called Apanteles congregatus, which lays its eggs in the caterpillars and keeps populations in check. Opportunistic birds also seem to relish "Catalpa worms," and it's not uncommon to see a Red-eyed Vireo (above left) or a Yellow-billed Cuckoo grab one and flop it around several times against a branch--pulverizing it enough so the parent bird can feed the whole caterpillar to one of its famished fledglings.

Fish and frass, moths and trees, caterpillars and birds--now you know how all these are wondrous examples of the many natural "Connections" at Hilton Pond Center.

Back to A Quiz on Connections

Ruby-throated Hummingbird--15*
Carolina Chickadee--1*
Eastern Bluebird--9 (all nestlings)
House Finch--14*
Carolina Wren--1*

* = Includes at least one Recent Fledgling

WEEKLY BANDING TOTAL
(8-14 July 2001)
5 species
40 individuals

* This is the third hummer banded in 1997 and recaptured in 2001; each was also recaptured every year in between.

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