The spectacled caiman got its name from the bony ridge between its eyes which give it the appearance of wearing a pair of glasses. These caiman can grow up to approximately nine feet in length, with females being of smaller size than males. They have a stout snout, and a triangular ridge of skin atop each eye which give the appearance of a type of 'eye brow'. Mature individuals are olive-green with faint black spots and banding on their tails, this coloration is usually more distinct in younger individuals. Its coloration overall is quite variable, with some individuals having different coloration, sizes, and skull shape - these features have led to distinction between three subspecies of spectacled caiman.
Range and Biology:
This species is widely distributed compared to other crocodilians. The spectacled caiman and its subspecies can be found in Mexico, Peru, Brazil, Venezuela, Columbia, Bolivia, and Ecuador - it has also been introduced as a nonnative species in Cuba, Puerto Rico, and Florida, USA. Theses animals thrive in all lowland wetland and riverine habitats, preferring bodies of still water like lakes, ponds, and marshes. They are also tolerant to moderate salinity.
The caiman is highly adapted for water life. It is a superb swimmer and aquatic predator. The adult caiman feed on fish, amphibians, reptiles, and water foul - particularly large individuals have also been know to take on mammals including deer and pigs! In dry conditions when food sources are scare this species is also known to cannibalize smaller individuals.
The spectacled caiman was first sighted in Florida in 1960, and span across two counties in the state. It poses threat to a variety of native vertebrates and competes for food and space with the native American alligators. They are presumed to have been released or escaped from the pet trade, and can be found in Broward and Dade counties throughout marshes, lakes, ponds, and canals. These crocodilian are susceptible to colder weather, which has confined them from moving further north. There have been efforts to remove the caiman populations, and in 2001 a nest of 41 eggs was found and collected, and 39 of those eggs hatched in captivity. Since 1970 there have been no reports of breeding, however the populations are still present.
Florida has more nonnative reptiles and amphibians than anywhere else in the world with more than 60 that are established and breeding. South Florida has a subtropical climate, island-like geography (water on three sides, frost to the north), major ports of trade which provide plants and animals entry into the United States, thriving trade in exotic pets, and occasional destructive hurricanes which increases risk of escapes.
Africa’s largest snake, the African rock python, are breeding in a small area of south Florida (estimated 6 square miles of land). The African rock python has a thick, long body, which is patterned in blotches that range from brown, olive, and yellow-toned tan, which form irregular stripes and chunky-block pattern. It has a triangular head and many sharp, backwardly curved teeth, and is covered in small smooth scales. Around the mouth are heat-sensitive pits, which are used to detect warm-blooded prey, even in the dark. African rock pythons are found throughout almost the whole of sub-Saharan Africa, from Senegal east to Ethiopia and Somalia and south to Namibia and South and western Africa.
Image: Edward Mercer, a non-native wildlife technician for Florida Fish and Wildlife Conservation Commission, holds a North African Python during a press conference in the Florida Everglades about the non-native species on January 29, 2015 in Miami, Florida (Image source: Jan. 28, 2015 - Source: Joe Raedle/Getty Images North America)
FWC In Florida, these snakes are a high priority species for management due to their large size and because of the extensive invasion of a similar species, the Burmese Python. They are very difficult to find, so determining how many north African rock pythons are present within the area is challenging.
Detection for the Burmese Python is between 0.005 and 0.01, and if we assume north African pythons are similar, then we would need over 300 visits to the area with no observations of pythons before it could be concluded with 95% confidence that the north African rock python population is not expanding.
There are efforts being carried out by Florida Fish and Wildlife Conservation Commission (FWC) and the University of Florida (UF) to research and remove the north African rock pythons from the wild in Florida. Biologists from FWC and UF, along with South Florida Water Management, and a handful of other organizations conduct surveys each week to locate these snakes. This year alone there have been two live captures of the African pythons, and one dead-on-arrival python which was run over with a commercial grade lawn mower. Recently, this species has been completely banned in the state of Florida, which means no new animals can be imported or exported from the state. Removal efforts have been in place since the first python sightings occurred in 2001, and banning this species will help keep these pythons from becoming as big a nuisance as the Burmese python.
More information on the Northern African rock python can be found by following the links below:
FWC Pest Brochure
Sun Sentinel News Article
What is EIRAMP?
This Everglades Invasive Reptile and Amphibian Monitoring Program (EIRAMP) was developed as a method for monitoring the spread of exotic species in southern Florida. South Florida is prone to invasion by nonnative species due to its sub-tropical climate; mosaic of agricultural, natural, and urban habitats; and island-like geography being surrounded by water on three sides and freezing temperatures to the north. The state of Florida alone currently hosts more established alien reptiles than any other state or nation (Meshaka et al. 2004). The natural portions of land are under increasing pressure from invasion by nonnative species, and current methods of interception and eradication of invaders has not been able to match the increasing threats.
Prevention of the introduction of invasive species is the best defense against invasions. Followed by the early detection of invaders and rapid response efforts towards their removal. Once populations are established and wide=spread the option for management becomes limited and expensive. Surveying current habitat for native amphibians, reptiles, and mammals alongside invasive species aids in determining the impact exotic species have in southern Florida. This monitoring program was developed to establish the status and spread of existing populations of invasive reptiles and amphibians, provides early detection and rapid response for removal of invasive species, and to provide information on the invasive animals collected while surveying.
The areas being surveyed have potential for detection of nonnative amphibians, reptiles, and mammals; there are currently 22 areas, with potential for additions if there are particular areas of concern. The surveys conducted once a month, within 30 minutes of sunset. While driving or walking, animal species that are observed are identified and recorded on a data sheet. This information, along with the GPS location, habitat type (parking lot, tree, road, etc.), and the number of individuals observed. Invasive animals (primarily Burmese Pythons) are removed when encountered.
Environmental information including time of night, temperature, humidity, and general weather (rainy, clear, cloudy) are also recorded. At the end of each survey the data recorded is entered into a computer database. Once in the database, all of the surveys can be sorted through. For example, I could ‘search’ for every animal seen under “cloudy” conditions; or for every “Burmese Python” that was encountered.
What Do We Learn?
All of the information recorded during these surveys is put towards management plans and other scientific studies. All of the categories of information can be analyzed for patterns. For example: Looking at temperature and species, we may see a pattern in what animals are seen at certain temperatures; or time of night; or weather...see what I'm saying? This information can then be used to supplement management plans for the removal or control of invasive animals; it can also be used to monitor the populations of native animals. If we see an increase in Burmese Python sightings over the years, and a decrease in the sighting of native snakes, it may imply that Burmese Python presence is influencing the presence of native snakes. This is very important information, especially when threatened species are involved.
The most important part of these surveys are the number of surveys carried out. The more surveys conducted over several years, the more information and patterns may emerge. Data from 2012 compared to data from 2017 may reveal shocking differences in the the number of invasive species encounters, or in the type of native species encountered (more mammals than reptiles?); it even can show a change in the weather or temperature over time (very wet or dry year; hot or colder?). All of this data is ever growing, and it is never going to become irrelevant. The more we know, the more we can do to help stop invasive animals from spreading.
Wildlife Trade is an industry that revolves around transport of animals to be utilized for multiple goods and services. The demand for live animals varies in different areas of the world, but the bottom line is that animals are traded A LOT. The figure below shows the number of animals imported into JUST the USA from 1999-2010. Pretty crazy, right?
With all of this trade going on there is bound to be consequences - animals are lost or escape from shipments. The release of these traded animals results in the spread of diseases. Chytrid fungus and rainavirus are decimating native amphibian populations, and both were spread due to the trade of wildlife. Not only can these diseases impact other animals, but the SARS virus and Avian flu are both diseases spread by animals to humans.
Trade of animals occurs legally and illegally, and can result in over exploitation of wild populations. The trade industry is unsustainable, and it is one of the biggest threats to biodiversity. An even bigger threat to biodiversity is the invasion of nonnative species - a threat that is directly linked to the trade of wildlife. The trade of wildlife has increased gradually over many years - which means it is likely that nonnative introductions has increased as well.
I have hammered the threats posed by nonnative species in previous posts, especially when the nonnative species becomes an invasive one. Invasive species are any species (plants, animals, any organism) that cause economical damage, ecological damage, or threaten human health. The USA spends over $137 billion every year to manage these introduced animals even with all the regulations in place to monitor trade.
There are several policies that exist to protect wildlife from trade including:
- The Endangered SPecies Act
-Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITIES)
-Migratory Bird Act
-Wild Bird Conservation Act
These, along with various regulations at the state level, are put in place to prevent introduction, but it is not so simple. There is much man power, money, and time that is needed to dedicate for preventing introduction of species - and there is a lack of money to pay for the man power to monitor ALL of the shipments and trade involving flora and fauna; not to mention any escaped or released pets.
The demand for live animal trade is desired all over the world - from food to boots to ancient medicinal cures, live animals are wanted everywhere. This wildlife trade has introduced many species all over the world, not just in the USA. Australia, England, Guam, Japan, China, Puerto Rico, and many other countries are experiencing the impacts of nonnative specie introductions. The wildlife trade will never be shut down, but the depletion of wild animals will surly cause the market to crash.
I encourage the purchase of captive-bred (CB) animals. Although hard to find for some unique species, captive bred pets do not support the wildlife trade or depletion of wild populations. Every little bit of effort counts, support your local breeders!
*****This post has adapted a powerpoint presentation given by Dr. Christina Romagosa on wildlife trade. The information provided is my summary of her presentation that was given to a college Conservation Biology course earlier this year.*****
To keep with the theme of "animals that don't belong in Florida" I would like to introduce the Nile Monitor. Nile Monitors (Varanus niloticus) are large African lizards, which have been introduced in Florida via the pet trade - just like everything else, what a surprise. These carnivorous lizards can grow up to 8 feet in length, and weigh a whopping 30 pounds! They are diet generalists - meaning they will eat pretty much ANYTHING. I personally have been looking at some of their diet items, and they range from reptile eggs, to turtle, insects, small mammals, frogs, toads, and snakes!
These lizards were first noticed in Florida in the 1990s, and there is a heavy threat these lizards pose to a protected native species. In Africa, Nile Monitor are known to raid crocodile nests and feed on crocodile hatchlings - this feeding habit directly implicated Nile Monitors as threats to Florida's native American Crocodile. The American Crocodile is a protected species, and are recovering from a steep population decline that hit its lowest in the 1970s. Established populations of Nile Monitors could make it even harder for these crocodiles to recover.
These lizards are sold in the pet trade despite their rather aggressive demeanor. They are certainly not for beginners. To quote a book:
"There are few of these lizards less suited to life in captivity than the Nile monitor. Buffrenil (1992) considered that, when fighting for its life, a Nile Monitor was a more dangerous adversary than a crocodile of a similar size. Their care presents particular problems on account of the lizards' enormous size and lively dispositions. Very few of the people who buy brightly-coloured baby Nile Monitors can be aware that, within a couple of years, their purchase will have turned into an enormous, ferocious carnivore, quite capable of breaking the family cat's neck with a single snap and swallowing it whole."
-Bennett, D. 1995. Little Book of Monitor Lizards, Viper Press, Aberdeen, UK
As if their attitude wasn't enough, these lizards have huge appetites, require large space for housing (hello- they can grow to be 8 feet long...a tank over 16 feet in length would be required to comfortably house a lizard of that size!), and a very secure space at that. These animals also really enjoy swimming, climb, and dig - so pet owners should be ready to build an outdoor enclosure or dedicate a whole bedroom to their animal. This, of course, is why monitors are now a problem in Florida. The requirements the need to be kept, as well as the rude personalities, lead to owners becoming fed up, tired of, or just plain scared of their pet Nile Monitor. That is how they became to live in Florida - released pets.
To learn more about Nile Monitors as pets:
To learn more about Nile Monitors as threats:
All photos belong to Nick Scobel: https://www.flickr.com/photos/michiganherper/
Veiled Chameleon (above) found in Florida. Photograph by Nick Scobel.
Chameleons were first detected in Florida in 2002. Chameleons are arboreal (tree swelling) lizards which are native to Africa, Madagascar, southern Europe, and southeast Asia. They have prehensile tails which they use to hold onto tree branches, and cone-shapped eyes that can swivel in different directions allowing them to look two ways at once. There have been several species of Chameleon’s found loose in Florida including the Senegal Chameleon, White-lined Chameleon, Oustalet’s Chameleon, Panther Chameleon, Jackson’s Chameleon, and Meller’s Chameleon. While many have been seen, only two species are known to have isolated populations in Florida – the Oustalet’s and Veiled Chameleons.
Oustalet’s Chameleons are Madagascar natives and are one of the largest species of chameleons in the world. Male individuals can grow to be over 24 inches long, and females stay quite a bit smaller.
A very detailed fact sheet on the Oustalet’s Chameleon’s is provided by the Maryland Zoo and can be found here: http://www.marylandzoo.org/assets/Oustalets-Chamelon-Fact-Sheet-2014.pdf
Veiled Chameleon’s are native to the Arabian Peninsula. This very pretty species have large domes on their heads, and can reac 12-24 inches in length. Hatchlings are pastel green, but as they grow these animals become a beautiful array of yellow, blue, orange, and black with white mottling seen in females.
More information on these animals can be found here: http://www.animalspot.net/veiled-chameleon.html
Oustalet's Chameleon found in Florida. Photographed by Christopher Gillette.
While Chameleon’s are still nonnative to Florida’s ecosystems, their threat to native animals has not thoroughly been explored yet. They are known to eat insects, small frogs, lizards, and small birds, which indicates they are competing with native lizards for food and a potential threat to smaller birds. Studies so far have shown the Oustalet’s Chameleons to eat agricultural pests and nonnative animals, however that could change depending on the location of the population. In Hawaii, the Veiled chameleon is a threat to native birds, insects, and plants – which leaves room for concern for the Florida ecosystem.
An issue associated with the removal of these animals from Florida’s wild is that people tend to move them to different locations (causing spread to new areas). People also are responsible for the introduction of more species, which makes eradication of these animals in the wild a constant effort. Right now Chameleons have been found in Florida City, Fort Meyers, and other species have been found in Lee, Collier, Miami-Dade, and Broward counties.
Although Chameleons have not made a huge hit to the ecosystem in Florida yet, they easily could be the next "Burmese Python" and wipe out prey species for other natives, and in doing so drive the native animals to dwindling numbers. These nonnative animals do not belong here- and even without a proven impact, in 20 or 30 years they may be the next "Florida Invader". It is a very sad thought that humans are causing the decline in native animals here in Florida - as a pet owner, please remember to not release your pets! Re-home them, donate them, or bring them back to pet store facilities where they were purchased. Please be a responsible pet owner and don't let them loose!
About the Author:
Jenna is a Wildlife Ecology and Conservation student at the University of Florida. Her primary work is research, control, and removal of nonnative and invasive animals found throughout south Florida.
Argentine black and white Tegu’s are large lizards native to South America – specifically Brazil, Paraguay, Uruguay, and Argentina. These reptiles can reach up to four feet in length, spend most of their time on land, but can swim and remain submerged for long periods. These critters are intelligent, and when kept as house pets can be very attached to their owners and quite docile.
Many people buy these animals when they are tiny hatchlings, and do not do their research. As they grow and become more work than their owners care to give, many owners become irresponsible and release their Tegu into the wild. This terrible practice has given Florida yet another ecosystem disaster.
Wild Tegus are a huge threat to the ecosystems in Florida. Tegus have breeding populations in Miami-Dade and Hillsborough counties, and the main concern is that these animals will compete with and prey upon Florida’s native wildlife including threatened species. Tegu’s reproduce quickly, and females can lay up to 35 eggs a year. They eat a wide variety of items including small animals and eggs, which raises the concern that they will eat the eggs of many bird species. So far it has been documented that these animals have eaten Alligator eggs, which raises concern for Crocodile conservationists – what if these invasive animals prey upon the eggs of American Crocodiles? FYI American Crocodiles are a threatened species.
To prevent the spread of these animals Florida Fish and Wildlife Conservation Commission (FWC) is working with other Florida agencies and organizations to assess the threat of this species and develop management strategies. I am part of the wildlife ecology and conservation lab in the University of Florida, and part of my job is to trap and remove wild Tegus. We have over 150 live traps set to capture these lizards, and bring in anywhere from 5-13 Tegus a day. We have removed over 2100 Tegus to date. It certainly is not a glamorous job – wild Tegus are very aggressive when trapped, and have strong jaws that will rip open your flesh (yes, it hurts, A LOT), but someone has to do it.
As I urged in my last post regarding Burmese pythons: Please, do not release your pets into the wild. Be a responsible pet owner – Don’t let it loose.
You can read more about the UF efforts to rid Florida of Tegus here:
About the Author:
Jenna is a Wildlife Ecology and Conservation student at the University of Florida. She primarily works with research, removal, and general management of nonnative and invasive species in south Florida.
The Burmese Python (Python bivittatus), is a snake that is found naturally occurring in a large area of tropical South and Southeast Asia. Their average lifespan in the wild is 20-25 years (NationalGeographic.com), grow to be 16ft-23ft in length, and can weigh an upwards of 200lbs. These snakes are very popular in the pet trade and can be purchased quite easily.
Here in Florida, however, they have become a nuisance. Between raging storms destroying warehouses and freeing the captive pythons, and careless owners releasing their pets into the wild once they reach an unmanageable size, the Burmese python has an established population in south Florida – mainly in the Everglades.
Over 2,000 pythons have been removed from the Everglades National Park (ww.nps.gov) since 2002. This is only a tiny portion of the population that is present down here in south Florida. The pythons have inflicted a devastating impact on the ecosystem in the Everglades – these snakes have feasted on the native birds, mammals, and reptiles found in the ‘glades. This includes the previously endangered Wood Storks, which are currently listed as a “threatened” species (and are imperiled in the state of Florida). Below is an image showing what a Burmese python needs to consume in order to grow to be 13ft.
Many agencies in Florida are doing their best to remove pythons from the Everglades in an attempt to save Florida’s wild life. Florida Fish and Wildlife conducts surveys and rapid response to remove pythons from the everglades and peoples’ properties.
You can read more about FWC’s involvement HERE.
University of Florida currently is permitted to remove Burmese pythons that are encountered, as well as carry out surveys to find pythons. Recently they endeavored to bring in two Indian Tribesmen to help catch pythons!
You can read more about the Indian Tribesmen HERE.
And more about University of Florida’s involvement HERE and HERE.
Most recently, South Florida Water Management District (SFWMD) has developed a Pilot Python Elimination Program where they paid a select few individuals (who applied and were selected as good candidates) to catch and remove pythons from SFWMD lands.
You can read more about the SFWMD program HERE.
Burmese pythons are the perfect example of why pet owners should do major research before investing in purchasing an animal to keep as their own. This snake has proven to be a HUGE damage to the Florida ecosystems. Wildlife is declining – wood storks, song birds, alligators, bobcats, deer, marsh rabbits, and even other snakes have all been diet items found inside the pythons. This animal has cause some very real problems for the state of Florida, and I urge everyone to please take appropriate measures when you are considering buying, selling, and re-homing your animal. Be a responsible pet owner, DON’T LET IT LOOSE!
An interactive map of python sightings in Florida can be found HERE.
Photos are courtesy of myself and Nick Scobel (www.flickr.com/photos/michiganherper/)
About the author: Jenna is a Wildlife Ecology and Conservation student at the University of Florida. Her primary work is research, removal, and management of nonnative and invasive animals in south Florida.
Hello All! My name is Jenna, and I am a wildlife conservation student currently pursuing a Master's degree at the University of Florida - you can read more about me in my bio! I am here today to write a general overview of the topic which I am focusing most of my time and energy towards as a student: Invasive animals.
What is an invasive species?
To understand what an invasive species is, we first need to recognize that invasive species are only animals which are not native to the area they have invaded. Nonnative species are any introduced, alien, or exotic species living beyond its native geographic range. A nonnative species is not necessarily an "invasive species", but an invasive species MUST be a nonnative one.
Invasive Species are any plant or animal that is not native to an environment, which steadily proliferates until it is taking over the native landscape/ecosystems.
These "invaders" become established, reproduce, and wreak havoc on the native species in an area. The area I will be focusing on a quite a hot spot - FLORIDA! Florida is easily suceptable to alien invasions, and many species that are already introduced present novel difficulties for management, or have other characteristics making effective management extremely challenging (Engeman et al. 2011). The Sunshine State has become a mixing pot for nonnative animals - there are all sorts of pets and so-called "zoo animals" which have been released. From parrots, Lion fish, and monkeys, to Pythons, Caiman, Argentine Tegus, and Chameleons - Florida is full of nonnative invaders.
Why are they in Florida? Where did they come from?
It is easy to say that these critters have been introduced in Florida through human interference - brought over on a boat importing goods or escaped/released/abandoned pets being the most common methods of introduction (myFWC.com). I have been told stories by acquaintances in Maryland (my home state) of how they went on vacation and dumped their neighbor's Boa constrictors on the side of interstate - they were doing the "neighborly thing" by dumping these pets in an area where they had a chance of surviving rather than rehoming or humanely euthanizing them.
Unfortunately for poor Florida, it is now facing a huge problem. The boas and pythons are picking off the native mammals one-by-one (Dorcas et al. 2011), and the giant lizards (the Argentine Tegu and the Nile Monitor) are quickly moving in to pick-off a few other native animals as well.
Which nonnative animals in Florida are the most prevalent/problematic?
Burmese Python (INVASIVE!)
Argentine Tegu (INVASIVE)
Nile Monitor (INVASIVE)
Chameleons (not invasive, just nonnative!)
Stay tuned for posts detailing the impacts these problematic critters are having on Florida's native ecosystems!
About the blog
Ferrets and Friends, LLC has four writers bringing you information on a variety of topics from pets to wildlife, education to conservation, and from new developments in our business to information about our industry. Learn something new each week!