Divided We Fall
Noah Altman | December 2019
Technology for tracking animal populations has come a long way since its inception. Devices like radio collars, and strategies like population sampling, can help us determine important details about a species: things like range, population size, population rate of change, etc. Usually, when tracking animal populations for large mammals, researchers go to great lengths to maintain the safety of the animal and create as little disturbance to the natural habitat as possible. In 2015, a group of researchers were able to measure the Florida Panther population in the least invasive way possible and with relative precision; they only used existing data. In order to estimate the population size of the endangered Florida Panther, these researchers used public reports of motor vehicle collision mortalities. They had a lot of data to work with.
This might not surprise you if you’ve ever taken a drive into southern Florida and seen the yellow road signs along the highway depicting the black silhouette of a large cat with text below the image reading “next mile” or “next 10 miles”. Contact with humans is exceedingly rare, but contact with human-made structures and vehicles is anything but. Once the panther leaves the confines of the everglades, perhaps the last remaining suitable panther habitat, they are out of their safe and navigable environment, and in danger. To the surprise of no one, panthers are not adapted to avoiding private property and traffic. They are, on the other hand, adapted to a variety of natural landscapes.
The Florida panther is a federally endangered subspecies of Puma, the last remaining in the southeastern United States. This large cat can get up to 7 feet long and 150 pounds. Panthers require large tracts of contiguous land for survival; their reproductive success is correlated with land ownership. Strict carnivores, their diet is primarily composed of feral hogs, deer, and raccoons. They are opportunistic predators, often praying upon sick or injured animals, as well as livestock. Despite their opportunistic nature, you would be hard pressed to find a more impressive hunter; Puma concolor coryi is capable of moving around their forest environment like a ninja, silently stalking prey, climbing trees, and crossing uneven terrain with ease. Their tan coats provide good general camouflage for their habitat, and their longer hind legs make them impressive jumpers. Using their killer arsenal, they can take down pray 2.4 times their size, including the formidable opponent, the florida alligator.
Unlike many other top predators, the presence of more Florida panthers will not usually mean the demise of their prey populations. For this reason, they are a valuable keystone predator. Historically, their range extended across the entire American southeast, from Arkansas to Florida to South Carolina. Today, they only persist in southern Florida, less than 5% of their historic range, with upper population estimates of 230 panthers.
The switch flipped around the same time Florida became a popular place to visit and do business. In the late 1800’s, tourists visited florida for the beautiful beaches, forests, and wildlife populations. If you weren’t a tourist, you came to Florida for large-scale agriculture, mining, and cigar manufacturing, which were taking off and rapidly growing the economy. This expansion required the growth of the co-requisite transportation industry. After World War 1, land developers descended on the state, completely transforming the land into a more “modern” Florida. More tourists meant more hunters, and hunters had already made a significant dent in the panther population for the entire southeast. Eventually, this one particular species of panther that once bred and exchanged genetic information with other panther species found itself backed into a corner in southern Florida with a population of less than 50. The Florida panther had been pushed behind the walls of this new human derived, and human-suitable, landscape.
Land development almost always causes habitat fragmentation. Habitat fragmentation on the development scale occurs when the flow of one inhabited area is disrupted, in this case (and nearly every case) by buildings, roads, bridges, and other large impervious surfaces. Disrupting the flow of an ecosystem on land is effectively like throwing a wrench at a rube-goldberg machine: it leaves you with multiple incomplete parts, and neither functions in the way that it originally did. When parts of an ecosystem are separated, this creates patches composed of smaller communities. These communities are more vulnerable to being wiped out by chance events. Any species that only live in the fragmented area will probably not survive. In order to find a breeding partner and obtain food, mammals like the Florida panther need to move between these isolated patches. The smaller the patches, and the further they are apart, the less likely they are to maintain their vulnerable populations. This means the Florida panther, with its vast, contiguous land requirements, takes a massive hit from land development.
The good news is that the population is steadily on the rise. The bad news is that this means nothing if the key threat of habitat encroachment is not aggressively pursued. Some methods of coadaptation have already been seen to yield success, such as constructing “habitat highways” that connect separated patches. These can take on the form of the wildlife crossing that allows large mammals, including the panther, to safely cross over highways in their own separate, enclosed path. The National Fish and Wildlife Service has a recovery plan that emphasizes the cats’ need for large protected areas, but these swathes of panther-friendly land are yet to be seen.
The Florida panther was not the first species to fall victim to habitat fragmentation, and it will not be the last. Every species of plant and animal is affected by habitat loss and fragmentation in some way, and the loss of one species means affects across the whole ecosystem. As long as humans live on this Earth, we will continue to make changes to the land, but there’s no limit on the creativity of people to come up with co-adaptive solutions. No building goes up without planning, no road is placed without reasoning and forethought; it’s about time we thought about how our friendly neighborhood panther fits into that process.
Sources
Bartareau, Tad, et al. “Growth in Body Length and Mass of the Florida Panther: An Evaluation of Different Models and Sexual Size Dimorphism.” Southeastern Naturalist, vol. 12, no. 1, 2013, pp. 27–40., doi:10.1656/058.012.0103.
Cayuela, Luis. “Fragmentation.” Encyclopedia of Islands, 1st ed., University of California Press, 2009, pp. 328–330.
Comiskey, E. Jane, et al. “Panthers and Forests in South Florida: an Ecological Perspective.” Conservation Ecology, vol. 6, no. 1, 2002, doi:10.5751/es-00406-060118.
Downs, Joni, et al. “Strategically Locating Wildlife Crossing Structures for Florida Panthers Using Maximal Covering Approaches.” Transactions in GIS, vol. 18, no. 1, May 2013, pp. 46–65., doi:10.1111/tgis.12005.
Frakes, Robert A., et al. “Landscape Analysis of Adult Florida Panther Habitat.” Plos One, vol. 10, no. 7, 2015, doi:10.1371/journal.pone.0133044.
Jacobs, Caitlin E., and Martin B. Main. “A Conservation-Based Approach to Compensation for Livestock Depredation: The Florida Panther Case Study.” Plos One, vol. 10, no. 9, 2015, doi:10.1371/journal.pone.0139203.
McClintock, Brett T., et al. “Endangered Florida Panther Population Size Determined from Public Reports of Motor Vehicle Collision Mortalities.” Journal of Applied Ecology, vol. 52, no. 4, 2015, pp. 893–901., doi:10.1111/1365-2664.12438.
“Florida Panther - Florida Panther - U.S. Fish and Wildlife Service.” U.S. Fish & Wildlife
Service, USFWS, Jan. 2018, https://www.fws.gov/refuge/florida_panther/wah/panther.html.
Noah Altman | December 2019
Technology for tracking animal populations has come a long way since its inception. Devices like radio collars, and strategies like population sampling, can help us determine important details about a species: things like range, population size, population rate of change, etc. Usually, when tracking animal populations for large mammals, researchers go to great lengths to maintain the safety of the animal and create as little disturbance to the natural habitat as possible. In 2015, a group of researchers were able to measure the Florida Panther population in the least invasive way possible and with relative precision; they only used existing data. In order to estimate the population size of the endangered Florida Panther, these researchers used public reports of motor vehicle collision mortalities. They had a lot of data to work with.
This might not surprise you if you’ve ever taken a drive into southern Florida and seen the yellow road signs along the highway depicting the black silhouette of a large cat with text below the image reading “next mile” or “next 10 miles”. Contact with humans is exceedingly rare, but contact with human-made structures and vehicles is anything but. Once the panther leaves the confines of the everglades, perhaps the last remaining suitable panther habitat, they are out of their safe and navigable environment, and in danger. To the surprise of no one, panthers are not adapted to avoiding private property and traffic. They are, on the other hand, adapted to a variety of natural landscapes.
The Florida panther is a federally endangered subspecies of Puma, the last remaining in the southeastern United States. This large cat can get up to 7 feet long and 150 pounds. Panthers require large tracts of contiguous land for survival; their reproductive success is correlated with land ownership. Strict carnivores, their diet is primarily composed of feral hogs, deer, and raccoons. They are opportunistic predators, often praying upon sick or injured animals, as well as livestock. Despite their opportunistic nature, you would be hard pressed to find a more impressive hunter; Puma concolor coryi is capable of moving around their forest environment like a ninja, silently stalking prey, climbing trees, and crossing uneven terrain with ease. Their tan coats provide good general camouflage for their habitat, and their longer hind legs make them impressive jumpers. Using their killer arsenal, they can take down pray 2.4 times their size, including the formidable opponent, the florida alligator.
Unlike many other top predators, the presence of more Florida panthers will not usually mean the demise of their prey populations. For this reason, they are a valuable keystone predator. Historically, their range extended across the entire American southeast, from Arkansas to Florida to South Carolina. Today, they only persist in southern Florida, less than 5% of their historic range, with upper population estimates of 230 panthers.
The switch flipped around the same time Florida became a popular place to visit and do business. In the late 1800’s, tourists visited florida for the beautiful beaches, forests, and wildlife populations. If you weren’t a tourist, you came to Florida for large-scale agriculture, mining, and cigar manufacturing, which were taking off and rapidly growing the economy. This expansion required the growth of the co-requisite transportation industry. After World War 1, land developers descended on the state, completely transforming the land into a more “modern” Florida. More tourists meant more hunters, and hunters had already made a significant dent in the panther population for the entire southeast. Eventually, this one particular species of panther that once bred and exchanged genetic information with other panther species found itself backed into a corner in southern Florida with a population of less than 50. The Florida panther had been pushed behind the walls of this new human derived, and human-suitable, landscape.
Land development almost always causes habitat fragmentation. Habitat fragmentation on the development scale occurs when the flow of one inhabited area is disrupted, in this case (and nearly every case) by buildings, roads, bridges, and other large impervious surfaces. Disrupting the flow of an ecosystem on land is effectively like throwing a wrench at a rube-goldberg machine: it leaves you with multiple incomplete parts, and neither functions in the way that it originally did. When parts of an ecosystem are separated, this creates patches composed of smaller communities. These communities are more vulnerable to being wiped out by chance events. Any species that only live in the fragmented area will probably not survive. In order to find a breeding partner and obtain food, mammals like the Florida panther need to move between these isolated patches. The smaller the patches, and the further they are apart, the less likely they are to maintain their vulnerable populations. This means the Florida panther, with its vast, contiguous land requirements, takes a massive hit from land development.
The good news is that the population is steadily on the rise. The bad news is that this means nothing if the key threat of habitat encroachment is not aggressively pursued. Some methods of coadaptation have already been seen to yield success, such as constructing “habitat highways” that connect separated patches. These can take on the form of the wildlife crossing that allows large mammals, including the panther, to safely cross over highways in their own separate, enclosed path. The National Fish and Wildlife Service has a recovery plan that emphasizes the cats’ need for large protected areas, but these swathes of panther-friendly land are yet to be seen.
The Florida panther was not the first species to fall victim to habitat fragmentation, and it will not be the last. Every species of plant and animal is affected by habitat loss and fragmentation in some way, and the loss of one species means affects across the whole ecosystem. As long as humans live on this Earth, we will continue to make changes to the land, but there’s no limit on the creativity of people to come up with co-adaptive solutions. No building goes up without planning, no road is placed without reasoning and forethought; it’s about time we thought about how our friendly neighborhood panther fits into that process.
Sources
Bartareau, Tad, et al. “Growth in Body Length and Mass of the Florida Panther: An Evaluation of Different Models and Sexual Size Dimorphism.” Southeastern Naturalist, vol. 12, no. 1, 2013, pp. 27–40., doi:10.1656/058.012.0103.
Cayuela, Luis. “Fragmentation.” Encyclopedia of Islands, 1st ed., University of California Press, 2009, pp. 328–330.
Comiskey, E. Jane, et al. “Panthers and Forests in South Florida: an Ecological Perspective.” Conservation Ecology, vol. 6, no. 1, 2002, doi:10.5751/es-00406-060118.
Downs, Joni, et al. “Strategically Locating Wildlife Crossing Structures for Florida Panthers Using Maximal Covering Approaches.” Transactions in GIS, vol. 18, no. 1, May 2013, pp. 46–65., doi:10.1111/tgis.12005.
Frakes, Robert A., et al. “Landscape Analysis of Adult Florida Panther Habitat.” Plos One, vol. 10, no. 7, 2015, doi:10.1371/journal.pone.0133044.
Jacobs, Caitlin E., and Martin B. Main. “A Conservation-Based Approach to Compensation for Livestock Depredation: The Florida Panther Case Study.” Plos One, vol. 10, no. 9, 2015, doi:10.1371/journal.pone.0139203.
McClintock, Brett T., et al. “Endangered Florida Panther Population Size Determined from Public Reports of Motor Vehicle Collision Mortalities.” Journal of Applied Ecology, vol. 52, no. 4, 2015, pp. 893–901., doi:10.1111/1365-2664.12438.
“Florida Panther - Florida Panther - U.S. Fish and Wildlife Service.” U.S. Fish & Wildlife
Service, USFWS, Jan. 2018, https://www.fws.gov/refuge/florida_panther/wah/panther.html.