Manatee Mortality Case Study

A group of researchers collected data to support the theory that the overpopulation of snakes is killing off the mammal population. Ashley Townsend, National Geographic writes, “the python population has continued to grow at a remarkable rate and has caused great distress to the park 's ecosystem.” For this study, the researchers at the South Florida Water Management District recorded the rates of live and dead mammals during a nocturnal road survey and compared it to the 1996-1997 road surveys. Scientists for the South Florida Management District, stated, “Researchers noted that the animals in the park were dying at a greater rate since the python population has gotten so enormous.”

Manatees are heterotrophic, so they have to find other sources of food because they can't produce their own.

Attributed to the release of the exotic pet, the encroachment of the voracious species has already demonstrated its appetite for the indigenous fauna of the Everglades. It is now feared that with their migration to the Florida Keys, the

This exceptionally charismatic megafauna has become synonymous with Florida along with “snowbirds”, orange juice, and Mickey Mouse but the Florida manatee may not be as permanent as its counterparts. Since being declared as endangered, the Florida manatee, a subspecies of the West Indian manatee, has been at the center of conservation efforts throughout the east coast of the United States. While human involvement has been at the crux of the increasing population, it can be argued that the best way to save this species is by taking humans out of the picture altogether.

Historical levels of the Southern Resident Orca population are currently estimated to have been as high as 200 (Fisheries.noaa.gov, 2015). The population as of 31st December 2015 was calculated at just 84 individuals (Center for Whale Research, 2015). There is limited data on the population before the mid 70’s so it is unknown what the population pattern looked like prior to this. Appendix A shows a graph documenting the population data found by a census started in 1974, as well as modelled data from 1960 to 1974. The graph starts with a low population, possibly explained by the frequent capture of live animals for marine parks (National Oceanic and Atmospheric Administration, 2014, p. 3). After this period the graph shows fluctuations in the population, then a steady growth resulting in a peak in 1995, then a sharp decline – almost 20% until 2001. This fast decline is what prompted governments to first list the population a threatened (United States Environmental Agency, 2014). The population has remained stable in the following years but now has an endangered status (Fisheries.noaa.gov, 2015).

Thought to have been first introduced into the wild via pet owners (Dorcas & Wilson, 20011) have caused significant declines in mammal populations. An observational study conducted by Dorcas et al (2012), found a 90% reduction in encounter rates of a number of species including racoon, opossums, bob cats and white tailed deer over the period 2003-2011 in which Burmese python populations have increased. The introduction of the Burmese python has also caused a significant decline in bird species. A study conducted by Dove et al (2011) found remains of 25 different species of birds in the digestive tracts of 85 Burmese pythons collected from 2003-2008, 4 of which are of special concern in Florida and 1 the ‘Wood Stork’ is listed as endangered. Preying on native wildlife and competing with native predators has impacted the food web and trophic level dynamics of the ecological

The conservation of Udubia is a significant issue that needs to be dealt with promptly. There has been a decline in the marine wildlife surrounding the islands, which leads to a greater question; Why is this happening and what can we do to help? For one, fishing is a major concern. South of Tacominone, and to the east is where many tens and hundreds of tons of lobster and Rockfish accordingly, as well as hundreds of pounds Yelloweye Rockfish are being caught, and simultaneously a decline in the population of seals. There is a correspondence in the increased fishing yield numbers to the decreasing seal population. The dodo observed that 90% of manatees off the coast of Florida have scars on their backs due to the propellers of fishing boats.

Over the years many exotic or non-native animals have been introduced into the Florida Everglades. Many of Mickey Cray’s animals in the novel Chomp are animals not native to Florida. The vast majority of these creatures are illegally smuggled into Florida. These creatures are then introduced into the wild by irresponsible owners. They pose serious threats to the environment, damaging the natural equilibrium.

have 24-32 molars in the back of their mouths. The front molars are worn away

Many of its marshes, cypresses, and mangroves cover the majority of the wetland and an estimated number of 50 reptile species and 40 mammal species currently residing are either endangered, or worse, threatened for extinction. The Florida Panther, according to the National Park Service, has a successful breeding population; nonetheless, the “primary threats to the remaining population are habitat loss, fragmentation, and degradation” (para. 2). Due to the ongoing urban development, the panther became a well-known endangered human threat. An estimated 80-120 panthers are surviving

Through the ages people have seen the rapid decline of many different species. Unfortunately due to habitat loss, hunting, and other anthropocentric reasons the loss of wildlife is a norm in the world today. The southern region of the United States is just a remnant of the beautiful landscape that used to cover the area. One species that has seen a direct negative implication of the development in this landscape is the majestic Florida Panther. This creature has been slowly decreasing ever since the first settlers in 1539 (Silverstein et al., 1997). Throughout the 1900’s people were both encouraged, and often times paid, to hunt them (Silverstein et al., 1997). The panther is still in danger today due to the destruction of their habitat with

Burmese pythons, a dangerous species of snakes, are inhabiting Florida’s Everglades and negatively impacting the environment surrounding them. But let me tell you, they’re not here by mistake. Humans are leaving their ferocious Burmese pythons in Florida’s Everglades due to unfortunate pet ownership mishaps. Their extremely large bodies and sharp teeth make it easy for the snake to swallow prey, not to mention prey up to five times the size of its own head. These fierce snakes are changing the local animal activity and population, affecting people, and impacting the ecosystem.

Last year alone over 15% of the Florida manatee population was killed by a human in a preventable way (Pittman). These preventable ways include polluting the waters, the use of fishing nets, and the wrongful usage of motor boats. Manatees have also been on the endangered species list since 1973. They first made it onto this list because their entire population

In an attempt to test the idea of maternal care in the American alligator, Kushlan observed mothers and their offspring. Juveniles at the nest were captured and then lightly squeezed to elicit a call of distress, and the mother’s reactions were observed. In each of the three trials, the mother came to the juveniles rescue with a threatening ferocity. Kushlan’s study on maternal care provided solid evidence of post-hatchling parental care in Alligator

Sea otters, (Enhydra lutris), are considered a keystone species, and for this reason, can be useful indicators of nearshore ecosystem health (Kreuder et al. 2003). With the implementation of the Marine Mammal Protection Act, southern sea otter (Enhydra lutris nereis) populations within their California range rebounded from post fur trade levels of approximately 50-60 in 1938, to more than 3000 today. However, growth rates have been slower than expected for this population (Riedman and Estes 1990). Definitive explanation for this is unclear, but contributing factors may be that sea otters face a range of physiological and environmental challenges to reproduce.