Chapter III — Species of Special Concern 



the Corps and the Water Management District under 

 a cost-sharing agreement. On 20 June 1995 the 

 Commission responded, commending the Corps for its 

 attention to this urgent conservation problem and for 

 its efforts to develop and apply innovative solutions in 

 a timely manner. In light of remaining technical 

 problems and limited experience with the improved 

 mechanisms, the Commission recommended that the 

 Corps adopt a flexible approach that would allow 

 construction schedules to be altered as necessary to 

 incorporate refinements that may become apparent as 

 new devices come online. 



While the Corps was developing plans to further 

 test and install gate reversal systems, the Water 

 Management District continued to experience fouling 

 and maintenance problems with the modified plunger 

 mechanisms. It therefore contracted for a study to 

 assess a promising new triggering mechanism with no 

 moving parts that might replace the plunger designs. 

 The new approach relies on a strip of piezoelectric 

 film — a tough plastic material that converts mechani- 

 cal pressure, such as that from an object pinned in a 

 closing door, into an electric current that could 

 activate the reversing mechanism. The study report 

 suggested that the film may well be a feasible, cost- 

 effective alternative. Therefore, at the end of 1995 

 the District was developing specifications to test the 

 new approach in 1996. 



Manatee Rescue, Rehabilitation, and Release 



Every year Federal and State officials respond to 

 numerous reports of injured and distressed manatees. 

 In some cases injuries or problems are minor or 

 temporary and require no intervention. In other 

 cases, however, animals must be handled or treated, 

 and are either released on the spot or captured for a 

 period of more intensive care in captivity. Most cases 

 requiring intervention involve animals that are injured 

 by boats, entangled in ropes or nets, or orphaned and 

 unable to survive on their own. The number of 

 rescue attempts in recent years has generally ranged 

 from about 15 to 25 annually. However, in 1994 

 only 14 rescue attempts were made, while in 1995 the 

 number rose sharply to more than 50 attempts. The 

 leading causes for rescues in 1995 were collisions 

 with boats and entanglement in crab pot float lines. 

 The cause of the high entanglement rate, which 



increased markedly from previous years, is unclear 

 but may reflect a shift in fishing effort prompted by a 

 1994 ban on fishing with gillnets in state waters. As 

 of the end of 1995, 18 of the rescued animals had 

 died from their injuries and 19 had been treated and 

 released. 



To care for injured and distressed animals that 

 must be brought into captivity, the Fish and Wildlife 

 Service has authorized five Florida facilities (EPCOT, 

 Lowry Park Zoo, the Miami Seaquarium, Sea World, 

 Inc., and the Homosassa Springs State Wildlife Park) 

 to maintain animals under an Endangered Species Act 

 species enhancement permit. Although most animals 

 brought into captivity are released within a few weeks 

 to a year, some animals have been kept permanently 

 because of the nature of their injuries or because of 

 concern that they lacked or had lost skills necessary 

 for survival in the wild. Over the years the number 

 of animals judged to be unreleasable has increased, 

 making space to treat new animals very limited. 



As of the end of 1995, 46 animals were being held 

 at the five facilities. To help speed release of rehabili- 

 tated animals and to assess the potential of releasing 

 animals previously judged to be unreleasable, the 

 Service constructed a "soft release" facility in 1994. 

 Located in the upper Banana River within the Kenne- 

 dy Space Center on Florida's east coast, the pen 

 provides an opportunity for animals to adjust to 

 natural conditions and foods while they remain under 

 observation to ensure they are adapting. It is hoped 

 that 10 to 12 animals, particularly animals previously 

 judged unreleasable, might be released annually 

 through the pen. 



In August 1994 a rehabilitated adult male held in 

 captivity for four months and two young orphaned 

 calves were placed in the soft-release pen as an initial 

 test. Over the next several weeks all three adjusted 

 well and began feeding on seagrasses in the enclo- 

 sures. Late in August the adult male was released and 

 tracked with a satellite transmitter. It readapted 

 quickly to the wild. The two orphaned calves, 

 however, were not released because of the approach- 

 ing winter and concern that time was short for them 

 to associate with wild animals that could lead them to 

 a warm-water refuge. They were therefore returned 

 to captive facilities for the winter. 



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