Gill Maggots What is it Gill maggots parasitic

Gill Maggots

What is it? • Gill maggots • parasitic copepod in the genus Achtheres Parasitic copepod from Cherokee Reservoir, TN largemouth – Jim Negus Photo by Jim Negus, TWRA, Norris Reservoir Striped Bass, December 2003

Umbrella shaped bulla Modified maxillae Reduced mouth parts No legs and little segmentation Egg sacs Female * Mature males are much smaller and are free swimming

Life Cycle • Females produce eggs in eggs sacs • Nauplii stages are passed within the egg sac • First copepodid stage is released from the egg sac and is free swimming plankter. • After a short while they attach to fish and mature to adults • Females remain attached, males mature and become free swimming. • Free swimming males attach to females during copulation.

2000 Watts Barr Reservoir, TN - striped bass 2000 Tim’s Ford Reservoir, TN - striped bass Recent Reported Infestations 2001 Melton Hill Reservoir, TN - striped bass 2001 Watauga Reservoir, TN - 1 smallmouth bass 2002 Old Hickory Reservoir, TN - striped bass 2002 Norris Reservoir, TN - striped bass 2002 Smith Mountain Lake, VA - striped bass 2003 Kerr Reservoir, VA - striped bass 2003 Leesville Reservoir, VA - striped bass 2004 Lake Norman, NC - striped bass 2004 Gaston Reservoir, NC - striped bass 2004 Tellico Reservoir, TN - 1 striped bass 2004 Smith Mountain Lake, VA - largemouth 2005 Congaree & Saluda Rivers, SC striped bass 2005 Cherokee Reservoir, TN - white bass 2006 Ouachita Lake, AR - striped bass 2006 Fort Patrick Henry Reservoir, TN - striped bass (angler report) 2006 Keowee Reservoir, SC – spotted bass 2007 Cherokee Reservoir, TN - striped and hybrid striped bass 2007 Holston River - Cherokee Res. tailwater, TN - striped bass 2007 Santee Cooper, SC - striped bass 2008 Lake Murry, SC - striped bass

Myths 1) They kill fish. NOT! 2) They render fish non-eatable. NOT! 3) They spread to people who swim in the lake. NOT!

SCDNR Research

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