Friday, April 19, 2013

Roanoke Logperch mating video

Many of the fishes in our Mountain Stream exhibit have been displaying mating colors, but also have been actually mating. The video shows a small portion of the extended mating behaviors of our Roanoke logperch. In the foreground is a (presumably) gravid female and around her are several males in mating colors; their body banding becomes more pronounced and the red band on their dorsal becomes much more vivid. All the males (5) had been following this female the entire day, and this was the second mating session observed. The males jockeyed for position, arched their backs to show off their dorsals and nipped at each other waiting for her to settle in. Two different males appear to mate with the female.

We are proud to have these animals mate in our exhibit, not only because they are a Threatened and Endangered species, but because it is a strong indicator that we are providing them with ideal care.

Thursday, April 11, 2013

Juvenile brook trout video - beginning of collecting season

These are juvenile brook trout  in a side channel of the Tye River, approximately 200 yards downstream from Crabtree Falls. Native Virginia Brook trout spawn in late Fall, and take two to four months to hatch depending upon water temperature. After hatching, larval trout acquire food from their yolk sacs for a few weeks before becoming true free-swimming fry, like the ones in the video. They typically station themselves in a side current off the main stream flow facing upstream awaiting food to wash by. These young trout voraciously feed on aquatic insect larvae micro-crustaceans, and the occasional fish larvae. The Tye River has an excellent population of wild brook trout and the fry were abundant.

Banded sunfish Enneacanthus obesus can be beautiful aquarium fish

April is the month most native freshwater fishes become active and signals the beginning of our collecting season. This year we have only a few freshwater needs for the live collection: juvenile Lepomis spp., bowfin, a flathead catfish, a blue catfish, banded sunfish and some bluespotted sunfish that were captive bred by Nick Little at the National Aquarium in DC.