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“Dangerous” Insects and Invertebrates…and Why We Need Them!

Robberfly with PreyIf insects were to vanish, the environment would collapse into chaos”.  Expounding on this statement, noted entomologist E. O. Wilson went on to explain that, without insects and other invertebrates (animals without backbones), all life would grind to a halt.  Yet while many pollinate plants, provide us with medicines and are otherwise helpful, others are dangerously venomous, spread disease, and consume valuable crops.  But as we’ll see, harmful invertebrates are in the minority, and even they hold secrets that can be of immense value to humankind.

Astonishing Diversity

Mammals, birds and other well-known vertebrates comprise only 5% of the world’s animals…the balance is made up of insects, spiders, crabs, mites and an unimaginable diversity of other invertebrates.

Estimated at 30 million species, insects are the largest invertebrate group.  To put their numbers in context, consider this – the weight of insects in most African rainforests exceeds that of all resident vertebrates combined!  This statement takes into account such huge mammals as forest elephants and gorillas, and the incredibly numerous bats and rodents!   Insects are abundant outside the tropics as well – an acre of Pennsylvania soil may hold 425 million individuals, while New York is home to over 4,125 beetle species.  Read More »

Pet Trade Frogs Fund Conservation – Wikiri’s Unique Strategy

Marsupial FrogDecades of work in zoos and the pet trade has, I believe, given me a unique perspective on the contributions that each can make to amphibian conservation.  Over the years, I have been greatly influenced by the work of private keepers who, in some cases, bred rare species long before zoos. Indeed, numerous husbandry techniques used in zoos originated in the private sector. In general, however, the pet trade focuses on pets and conservationists focus on conservation. But Wikiri, an enterprise formed to support amphibian conservation and research, combines the best of both worlds by using captive-bred frogs to promote its goals. In doing so, Wikiri has broken new ground in addressing the amphibian extinction crisis.

Amphibian Declines

The threat currently facing amphibians are unprecedented. At least 200 species have become extinct in recent years, prompting some to compare this “Sixth Extinction Crisis” to the disappearance of the dinosaurs.  Read More »

Eastern Diamondback Rattlesnake Facts – the World’s Largest Rattler

Eastern DiamondbackToday I’d like to cover a snake that, while not suitable as a pet, stands out in the minds of many as North America’s most impressive serpent – the Eastern Diamondback (Crotalus adamanteus). In my youth, the nearby Staten Island Zoo’s Reptile House was under the direction of the legendary Carl Kauffeld.  The collection contained every known rattlesnake species but, somehow, a massive pair of Eastern Diamondbacks stood apart.  Several years ago, I was thrilled to be chosen as consultant for the renovation of this building , and Rattlesnakes, including the Eastern Diamondback, again take center stage there.

Description

The record length of this largest of the world’s 33 rattlesnake species is 8 feet, 3 inches; most adults top out at 3-6 feet.   In the USA, only the Indigo, Bull, Gopher and Black Rat Snakes approach or, very rarely, exceed this measurement.

The background color of this heavy-bodied, venomous snake ranges from olive through brown to (rarely) near-black.  The back is patterned in white-centered dark diamonds that are sharply outlined in cream or yellow.

Captives have lived in excess of 22 years, but longevity in the wild has not been well-studied. Read More »

Green Iguana Care – Housing, Diet and Handling

Green IguanaThe Green Iguana (Iguana iguana) is truly a study in contrasts.  Captive-bred by the millions on farms in Latin America, the 7-inch-long hatchlings are widely considered to be suitable for novice reptile keepers.  Indeed, with proper care, they mature into one of the most impressive and responsive of all reptilian pets.  Yet these tropical lizards have very specific needs that must be met if they are to thrive, and their eventual size (4-6 feet) and potentially aggressive behaviors are serious considerations.

Range and Habitat

The Green Iguana’s range extends from southern Mexicothrough Central America to Paraguay. They also inhabit Puerto Rico, St. Lucia and other Caribbean islands, and have been introduced to Florida and Hawaii (please see this article on Iguana-Raccoon Interactions in Florida).

Green Iguanas are always found near water, into which they plunge when frightened. They are often associated with forested areas, so I was surprised to encounter large populations in Venezuela’s treeless llanos region; please see this article.

Behavior

Green Iguanas are ever-alert, and easily startled by noises, dogs and other threats. They vary greatly in personality – some become docile, while others remain wary of people.

Frank with Green IguanaMales may become dangerously aggressive with during the breeding season (please see article below), and either sex may bite, lash out with the tail, or scratch.  The wound on my arm, pictured in the attached photo, resulted from a single flick of the tail (and my skin is generally described as “very leathery”!).  Please write in for information on safe handling.

Housing

Setting up the Terrarium

Enclosure size is a major concern.  Hatchlings will exceed 2 feet in length in their first year, and 3 feet by age 2.  Adults reach 4.0 to 5.5 feet in length, with males sometimes exceeding 6 feet.

Hatchlings may be started in a 30 gallon aquarium, but will need a 55 gallon tank within 12 months.  Once your lizard reaches 3 feet in length, a homemade or commercial cage will be necessary.  An enclosure measuring 6 x 3 x 6 feet tall will suffice for an adult; wheels should be added to allow for sun exposure.  Predator-proof outdoor cages such as modified bird aviaries are the ultimate in “luxury accommodations”.

Green Iguanas are highly arboreal and will be stressed if kept in enclosures that do not allow climbing opportunities.  Stout branches and wooden shelves should be provided.

If an “iguana proof” room is available, out-of-cage exercise time can add greatly to your lizard’s quality of life.

Substrate

Cypress mulch has been used with success, but impactions due to substrate ingestion are possible.  Newspapers, washable cage liners or outdoor carpets are preferable.

Females without access to suitable nesting sites may retain their eggs; please see this article for information on captive breeding.

Light

Green Iguanas will not thrive without a source of Ultra-Violet B light.  Natural sunlight is best, but be aware that glass and plastic filter out UVB rays, and fatal overheating can occur very quickly.

If a florescent bulb is used (the Zoo Med 10.0 UVB Bulb is ideal), be sure that your pet can bask within 6-12 inches of it.  Mercury vapor and halogen bulbs broadcast UVB over greater distances, and also provide beneficial UVA.

Heat

The ambient air temperature should range from 82-95 F, with a basking spot of 95-100 F.  Incandescent bulbs should be used to maintain these temperatures.  A ceramic heater or red/black night bulb can be used after dark.

Humidity

Green Iguanas favor humidity levels of 65-75%, but must be able to dry off as well.  The terrarium should be misted as needed.  A reptile humidifier may be used in especially dry environments.

A large water bowl should be provided for drinking and soaking.

Companions

Male Green Iguana during breeding seasonMales will fight savagely, and females may also battle for dominance.  Juveniles usually get along, but must be watched carefully as they mature.

Feeding

Strict attention to diet is essential if you are to succeed with Green Iguanas.  Nutritional deficiencies can develop quickly, and are difficult to treat. Young iguanas should be fed daily; 2 small meals are preferable to 1 large.  Adults can be fed every-other-day, or provided smaller daily meals.

Greens, Vegetables and Fruit

The majority of your iguana’s food – 60% or more – should consist of a variety of fibrous, calcium-rich vegetables such as kale, romaine, dandelion, bok choy, collards, mustard and turnip greens, beet tops and escarole; broccoli, peas, squash, beans, carrots, peppers and mixed frozen vegetables may be added in smaller quantities.  Spinach binds calcium and should be avoided.

Fruit should not comprise more than 10% of your iguana’s diet.  Bananas, pears, apple, figs, melons, berries, kiwi, peaches and others should be offered.

Boiled brown rice or fiber-rich, sugar free cereals (i.e. Fiber One) may be given as a fiber source. This may not be necessary if a variety of fibrous greens are provided, but serves well as “insurance”.

Protein

In their natural environment, young Green Iguanas consume both insects and vegetation before switching to a plant-based diet as they mature.  While success has been had by using insects as a protein source for young iguanas, most keepers are better off relying upon legumes, such as boiled lentils or pinto, navy and kidney beans.  These should make up 5-10% of the diet until age one, after which time they can be used as occasional treats.

A number of commercial iguana diets are available.  While their long-term use as a sole diet has not been studied, adding some to your iguana’s salad should provide additional nutrients.

Supplements

Most meals provided to growing iguanas should be powdered with a Calcium source such as Zoo Med ReptiCalcium.  Reptivite or a similar vitamin/mineral supplements should be used 2-3 times each week.  The supplementation needs of adults vary; please write in for further information.

Health Considerations

Due to their size, Green Iguanas are sometimes allowed to wander at will about the home.  While a room that has been carefully set up for your iguana (please write in for details) can be useful, free-ranging iguanas present serious health and safety risks.  Chief among these are the potential for fires (dislodged lamps, etc.) and an increased risk of Salmonella transmission.  Please write in for further information. Read More »

Lizard Conservation in the USA – 2012 Declared “Year of the Lizard”

Collared LizardThe Partnership for Amphibian and Reptile Conservation (PARC), a group comprised of private citizens, herpetologists, environmental organizations and others, has made great progress in the 10 years since its inception. 2011’s “Year of the Turtle” effort was especially effective in raising support for tortoise and turtle conservation. This year, the group has turned its attention to lizards, with an emphasis on North America’s many unique and imperiled species.

Lizard Conservation Overview

In the eye of the general public, lizards do not suffer the “image problem” that besets snakes, yet they lack the appeal of turtles and frogs. And so their conservation needs are, with few exceptions, not well-known. I sometimes wonder if the high visibility of a few common anoles and geckos in warm locales leads some (non-herp-oriented) people to regard lizard populations as relatively secure.  Read More »

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