Trout Love in the Spring — What is a “Redd”?

Posted on: May 2nd, 2019 by Leslie_Zucker

The wild Rain­bow Trout of the upper Eso­pus Creek are now spawn­ing – it’s spring! Here are the mechan­ics: a female trout digs a depres­sion in the grav­el with her tail called a “redd.” She deposits the eggs and waits for a male trout to fer­til­ize them, then she cov­ers the eggs with loose grav­el. They both swim away leav­ing the eggs shel­tered (unlike salmon, trout don’t die after spawn­ing). Rain­bow Trout spawn in late spring until tem­per­a­tures start to rise. Brown Trout and Brook Trout spawn in the fall.

A spe­cial note to anglers and any­one wad­ing streams this spring – be mind­ful of red­ds and don’t dis­turb them.

A redd should appear like a depres­sion with clean grav­el inside, and may be lighter or dark­er than the sur­round­ing grav­el (see the pho­tos below). Don’t walk through them and be care­ful where you wade. Red­ds in the upper Eso­pus Creek are often observed in the “tai­lout” of a pool.

In the par­lance of geo­mor­phol­o­gy, this stream bed fea­ture is called a “glide.” Glides are where the steeply sloped bed ris­ing out of a pool becomes flat­ter and water veloc­i­ty increas­es. Glides are locat­ed imme­di­ate­ly down­stream of pools.

Rainbow Trout Redd

Rain­bow Trout redd in the Bush­nellsville Creek, May 2018. Pho­to by Ed Ostapczuk.

Rainbow Trout Redd

Rain­bow Trout redd observed in a trib­u­tary to the upper Eso­pus Creek, April 2019. Pho­to by Ed Ostapczuk.

Glide with Rainbow Trout Redd

Loca­tion of the redd above in tai­lout of a pool. Pho­to by Ed Ostapczuk.