University of FloridaSolutions for Your Life

Download PDF
Publication #WEC293

Florida Invader: Nile Monitor Lizard1

Steve Johnson and Monica McGarrity2

Figure 1. 

Nile monitor (Varanus niloticus).


Credit:

Patrick Lynch, South Florida Water Management District, 2009


[Click thumbnail to enlarge.]

Report Nile Monitor sightings immediately:

1-888-IveGot1 (1-888-483-4681; live animals only)

www.IveGot1.org (provide photos if possible)

The Nile monitor lizard (Varanus niloticus), native to sub-Saharan Africa, has become established in the wild in coastal areas of Lee and Charlotte Counties in Florida due to releases or escapes of pets. There are also isolated populations in Broward and Miami-Dade Counties, and individual lizards of several Varanus species have been captured in other areas. Nile monitors are large, voracious predators that may grow to over 7 feet long. These large lizards eat the eggs of birds, alligators, crocodiles, and turtles and could impact many threatened and endangered species, including burrowing owls and sea turtles. They are opportunistic predators and will consume any prey they can subdue, including pets. They thrive in a wide variety of habitats near water, especially in and around urban areas, where they live in burrows near the water's edge. They are strong swimmers and spread via canal systems and coastal mangroves. Females lay eggs, which they bury. Lifespan is 10–15 years.

Identification

Learn to identify and report Nile monitors at http://ufwildlife.ifas.ufl.edu/reddy.shtml.

Figure 2. 

The Nile monitor's head is gray-brown and marked with light-colored, V-shaped marks across the neck—these marks extend forward through the eyes. The fleshy, forked tongue is blue. The narrow neck is longer than the head.


Credit:

Patrick Lynch, South Florida Water Management District, 2009


[Click thumbnail to enlarge.]

Figure 3. 

The Nile monitor's body is gray-brown and marked with bands of lighter-colored (often tan) spots with light speckles between them. Toward the end of the tail, the bands of spots fuse into solid bands.


Credit:

Patrick Lynch, South Florida Water Management District, 2009


[Click thumbnail to enlarge.]

Figure 4. 

Young Nile monitors look like the adults, but with a relatively larger head. At hatching they are nearly a foot long.


Credit:

Mike Pingleton, University of Illinois at Urbana-Champaign


[Click thumbnail to enlarge.]

Acknowledgments

This project was made possible in part by a grant from the South Florida National Parks Trust and the Ferris Greeney Family Foundation, and by the USDA-RREA. This document was created as additional reference material for the Introduced Reptile Early Detection and Documentation training program, also known as REDDy. For more information, visit http://ufwildlife.ifas.ufl.edu/reddy.shtml.

Footnotes

1.

This document is WEC293, one of a series of the Wildlife Ecology and Conservation Department, UF/IFAS Extension. Original publication date August 2010; revised February 2014. Visit the EDIS website at http://edis.ifas.ufl.edu.

2.

Steve A. Johnson, associate professor and Extension specialist, Department of Wildlife Ecology and Conservation, UF/IFAS Extension, Gainesville, FL 32611; and Monica McGarrity, extension program assistant, Department of Wildlife Ecology and Conservation, UF/IFAS Extension, Gainesville, FL 32611.

This fact sheet was made possible in part by a grant from the South Florida National Parks Trust and the Ferris Greeney Family Foundation, and by the USDA-RREA. Photos/Illustrations by Patrick Lynch (SFWMD) and Mike Pingleton (University of Illinois at Urbana-Champaign).


The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other UF/IFAS Extension publications, contact your county's UF/IFAS Extension office.

U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.