How to Manage Pests
Pests in Gardens and Landscapes
Lizards are common reptiles that mostly feed on insects. They can be fascinating creatures to watch, but trying to maintain them in captivity for any great length of time is difficult. Many will attempt to bite if roughly handled and their small, sharp teeth may puncture the skin, but otherwise, they are harmless to people. In fact, the only poisonous lizard in the entire United States is the Gila monster, which is found only in the desert regions of the southwest. On rare occasions, lizards may enter a home or garage and cause concern.
Lizards are the most abundant of the reptiles, comprising 3,000 species worldwide and over 60 types in California. They are recognized by their dry, scaly skin, four legs with clawed feet, and external ear openings. Unlike snakes, which are legless and can only slither, lizards run over the ground. Another difference between common snakes and lizards is in the eye. Most lizards have eyelids that close over the eye, while most local snakes do not have movable eyelids.
The most common genus of lizards in California is Sceloporus, most of which are in the blue-bellied group, including the western fence lizard. This lizard is one of the speediest and most versatile of the reptiles. It is also one of the most easily seen because during its active period (from April to October), it frequents rocks, trees, fences, and buildings. These lizards are 6 to 9 inches long and olive, brown, or black with a pattern of paired blotches or wavy cross bars or stripes down the back. The name "blue belly" comes from the blue patches on the sides of the belly. The adult male also has blue patches on the throat. By flattening his sides and raising his head, the male shows his blue marking to announce his sex and frighten away other males.
A common foothill resident is the alligator lizard, genus Elgaria (formerly called Gerrhonotus), that is 8 to 13 inches long and olive to brown. These lizards are primarily found in forested areas at elevations of 1,000 to 11,000 feet. They are not territorial and have a home range of 1 to 2 acres.
Although some lizards eat plants, most feed on insects. In California, the most common types feed on beetles, ants, wasps, aphids, grasshoppers, and spiders. Lizards cause no measurable damage to plants in gardens and should be left alone.
Lizards are generally egg layers, but one group, the horned lizards (horned "toads"), produce their young alive. The most common species of lizard in California, the western fence lizard (blue-bellied lizard, swift lizard), lays 3 to 20 cream-colored, soft-shelled eggs in pits of damp soil. These are generally laid from May to August, with the young hatching July to September. Lizards are cold-blooded and hibernate during winter months.
An interesting trait of lizards is their ability to break off or "throw" their tails when roughly handled or pursued by an enemy. The separated tail continues to wriggle while the rest of the lizard escapes. This seems to be a method of self-preservation and does no particular harm to the lizard. In time, a new tail will usually grow back.
LIZARDS IN THE HOME
Occasionally, lizards can enter homes and buildings through small openings, especially gaps beneath doors. They are excellent climbers so they can enter any structural opening 1/4 inch or larger.
Should a lizard enter your home, there are several ways to capture and release it outdoors. None of the methods is simple, so once the lizard is relocated outdoors, make sure it can’t reenter the home (see section below).
For the adventurous, there is a method known as "noosing." Noosing involves slipping a noose over the lizard’s head and gently tightening the noose to secure the lizard, which can then be safely carried outdoors and set free. This method requires a degree of skill because the noose must be slowly lowered over the lizard’s head without touching it and then quickly tightened by pulling upward and slightly backward before the lizard runs through the noose and escapes. Nooses can be made out of relatively stiff materials like dental floss or fish line. If using dental floss, it should be at least 3 feet long. The same with fish line — or a slender fishing pole can be used to hold and steady the line.
Another way to trap a lizard is to carefully put a small box over it. With the lizard in the box, gently slip a piece of cardboard under the box to cover the opening. Pick the entire unit up and take it outside.
Alligator lizards move somewhat slower than blue-bellied lizards and often can just be grabbed and taken outdoors. Because an alligator lizard does bite, wear a glove when you grab it.
KEEPING LIZARDS OUTDOORS
To prevent lizards from entering the home, seal all openings 1/4 inch and larger. Check areas such as corners of doors and windows, around water pipes, electrical service entrances, ventilation screens, water pipes, etc. Tight-fitting door seals, with no gaps at the edges, are important prevention measures. Unlike rats and mice, lizards cannot gnaw through wood and other common building materials. A number of materials can be used to seal access points, including insulating foam, caulking, flashing, and steel wool.
Good sanitation can be helpful in reducing the number of lizards around a home, although it alone will not eliminate their presence. Off-the-ground storage of lumber, crates, boxes, sacks, gardening equipment, and other household items will make an area less suitable for lizards by reducing their hiding spots
The taking and possession of lizards is regulated by the California Department of Fish and Game, with specific regulations depending on the species. Lizards cannot be sold or used for commercial purposes. For further information about taking and possession of lizards, contact your local Fish and Game warden.
There are no toxicants or repellents registered in California that can be used to kill or repel lizards.
Author: G. W. Hickman, UC Cooperative Extension, Mariposa Co.
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