Incidence of Human Interaction in Marine Mammal Strandings on the Texas Coast from 1980-1993
E.M. Haubold1; G.A.J.Worthy1; R.J.Tarpley2
The Texas Marine Mammal Stranding Network (TMMSN) was established in 1980 to document marine mammal strandings in Texas. Through 1993 it had responded to 1,542 strandings of which nineteen different species were identified. Since 1987, there has been an average of 167 strandings reported each year. Routine data collection included documenting the occurrence of "human interaction." Specific cases include boat propeller wounds, gunshots, net entanglements, and ingestion of man made objects. Since 1980, thirty-two animals of four species have been affected. In twenty-two of the incidents, human interactions were suspected to have lead to the death of the animal.
Seven animals were found entangled in nets, of which only one survived and was released. Five additional animals had marks suspected to be from nets. Nine animals had been shot, at least four fatally. Nine animals ingested foreign objects including plastic bags, monofilament line, fishhooks, and wire. Two animals were hit by boat propellers. One animal had a fishhook embedded in its flipper. At least eight other animals were butchered; "backstrap" muscle, dorsal fin, and/or head had been removed postmortem.
The relative incidence of suspected direct or indirect human induced mortality of marine mammals stranded in Texas was documented in only 1.43% of strandings.