Casitas -- manmade structures put on the sea floor to attract lobster -- may not be the environmental nightmare some feared, a new state study says.
"Lobster movement patterns do not appear to be affected by the presence of casitas," says a summary of the report, authored by John Hunt of the Florida Fish and Wildlife Research Institute.
However, there are an awful lot of the illegally placed casitas in Lower Keys waters, the report notes, and they do significantly change early-season catches by commercial fishers.
Hunt, a leading state lobster expert who heads the FWRI's Marathon office, will outline findings of the two-year study to the Fish and Wildlife Conservation Commission at the board's Wednesday meeting in Key Largo.
At the urging of commercial lobster divers in late 2006, the FWC asked its research agency to see if casitas could become legal gear as part of the regular fishery. State scientists worked with members of the Ecologically Concerned Commercial Divers of the Lower Keys group to gather information for the new report.
Taken from the Spanish for "little house," casitas are used to attract and aggregate lobster so divers can harvest them quickly and easily.
"The major impact of casitas on the lobster fishery is they increase the rate of lobster removal during the first month of the fishing season and therefore shift landings from trappers to divers," the report authors found.
Based on sample surveys, scientists estimate the study area -- 233 square miles in Gulf of Mexico waters north of the Lower Keys, generally 25 to 35 feet deep -- holds from 1,000 to 1,500 illegally placed casitas. Trap fishermen contend that large numbers of the artificial habitats might disrupt the lobsters' natural westward-moving migration through the Keys.
For the study, scientists outfitted a group of lobsters with small underwater transmitters tracked by sub-sea listening stations. The initial results suggest lobster did not halt their movement to take up permanent residence at a casita.
The study also concludes that casitas tend to remain relatively stationary, causing only minor changes to the hard bottom of the surrounding area. Small reef fish, primarily juvenile grunts, congregate around casitas in large numbers.
FWC staff will ask its board members: "Should staff begin a proposal for the use of casitas as a managed fishing gear in the commercial spiny lobster fishery?" If the agency seeks to further investigate legalizing casitas, the process could take years, staff cautioned.
A half-dozen state and federal agencies, including the Florida Keys National Marine Sanctuary, have some jurisdiction over the sea bottom around the Keys, the report notes.
Issues that would be raised include how many casitas could be placed, how they would be built and who would be licensed to take lobster from them.
A copy of the FWRI presentation on lobster casitas is available at Florida Fish and Wildlife Conservation Commission. The FWC board begins meetings at 8:30 a.m. Wednesday and Thursday at the Key Largo Grande Resort, mile marker 97 bayside.