Inbreeding is mating between close relatives. When a population of animals becomes isolated from other populations and its range restricted, inbreeding increases. Both of these circumstances have occurred with the Florida panther. It

"While other human related factors affect health of the panther's environment, it is now clear that genetic variability and health of the Florida panther must be restored for the taxon to survive even with adequate habitat preservation and other enhancement measures." Environmental Assessment: Genetic Management Options for the Florida Panther, 1994

has been isolated from other subspecies of cougar for at least 100 years and its range has been increasingly restricted by urban, suburban, and agricultural development. By the 1980s only 30-50 adults remained in the population. Under natural conditions, young male cougars may travel long distances from their places of birth to establish home ranges and to find mates. This not only decreases the probability that older dominant males will kill them but also decreases the chance that they will breed with a close relative. In south Florida, because of habitat fragmentation this option is not available to dispersing panthers, and close relatives have bred.

    A 1992 population analysis concluded that under existing demographic and genetic conditions the Florida panther would become extinct in only a few decades (24-63 years) (Seal et al. 1992). Congenital heart defects, poor sperm quality, and high incidence of cryptorchidism (one or two retained testicles that have not descended into the scrotum) have been cited as possible negative consequences of inbreeding among Florida panthers (Roelke 1991; Dunbar 1993).

One of the possible negative effects of inbreeding is abnormal sperm. Florida panthers have more abnormal sperm than individuals from other cougar populations. Compare the normal sperm to the defective ones. What's different about the abnormal sperm?

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Habitat Degradation    How Inbreeding Threatens a Population