Results from the Transplanting Studies of Queen Conch

During years of monitoring, we noticed that nearshore conch do not reproduce. All reproduction takes place offshore. Upon further examination, we found that nearshore conch are physiologically incapable of reproduction. They simply cannot make eggs or sperm. So, we came up with a pilot study where we transplanted some nearshore conch into offshore spawning aggregations. The results were astounding; after six months offshore, nearshore conch were mating and spawning - they had regained their reproductive abilities.

Transplanting nearshore conch offshore has several advantages over releasing hatchery juveniles: 1) it’s cheaper as there are no hatchery associated costs (food, electricity, etc), 2) it’s effects on restoration will be quicker as we are moving adult conch, not releasing juveniles, and 3) it will maintain the genetic integrity of the conch population because we are transplanting wild animals.

Spurred by this initial success, we decided to ramp up our next transplantation study. With the help of numerous TNC volunteers, almost 2,000 nearshore conch were transplanted to two offshore sites. The purpose of this study was to make sure that the transplanted conch would not displace the native conch and/or that the transplants would stay at their new sites and not wander away. The results from this project indicate that native offshore conch and transplanted conch remain in the same area and utilize similar habitats. The next question that needs to be addressed is where are the best places to transplant to ensure that the larvae produced from transplanted conch are retained within the Keys.

Why Don’t Conch Reproduce Nearshore?
In 2004, we will be initiating a twoyear study with our partners at the University of Florida and NOAA’s National Centers for Coastal Ocean Science to examine reproductive failure in nearshore conch. This study is funded by the U.S. Environmental Protection Agency Special Studies program. We will be examining the effects of estrogenlike compounds on conch reproductive physiology by exposing ‘normal’ conch to environmental contaminants and naturally occurring substances exuded from algae. This study is of particular interest as the results may have tremendous implications for coastal development not only in the Keys but also throughout the Caribbean where conch is the second most valuable commercial species.