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The Unique, Endangered Panamanian Golden Frog or Harlequin Toad – Part 2

Please see Part I of this article to learn about the natural history of the Panamanian Golden Frog , Atelopus zeteki, including it’s unique mode of communication.

Status of Wild Populations

Panamanian Golden Frog numbers are plummeting, most likely due to an epidemic of the largely incurable fungal infection
 Panamanian Golden Frog
Chitridiomycosis. The fungus responsible, Batrachochytrium dendrobatidis, has been implicated in the declines and extinctions of numerous amphibian species worldwide. This frog is also threatened by deforestation, stream siltation, pollution and collection for use as a promotional tool in Panama’s restaurant, hotel and tourism industries (this practice is illegal, but enforcement is often lax).

It is estimated that Golden Frog populations have declined by 80% in both numbers and extent of occurrence over a 10 year period. At least 2 distinct populations are extinct, with 1 such extinction occurring within the span of several months. Golden Frogs are designated as “Critically Endangered” by the IUCN and listed on Appendix I of CITES. They are legally protected by Panama and the subject of a cooperative rescue program, administered by the USA and the Republic of Panama, known as “Project Golden Frog”. Fortunately, the Golden Frog breeds well in captivity.

Unique Skin Toxins

This frog’s skin contains extremely virulent nerve toxins that differ from those produced by other amphibians. Known as “zetekitoxins”, the poison contained in the skin of a single 2-inch-long frog is sufficient to kill 1,200 mice! It is believed that these toxins are produced in association with symbiotic bacteria, but this has not yet been definitively documented.

Cultural Significance

The Panamanian Golden Frog is the national animal of the Republic of Panama, and has traditionally been associated with matters relating to good fortune. Pre-Columbian indigenous people molded its likeness in gold and clay talismans known as “huaces”.

Further Reading

You can learn more about Project Golden Frog by clicking here.

 

Tarantulas and Other Spiders – Dangerous vs. Beneficial Species – Part 2

In Part I of this article, we learned that less than 1% of the world’s 40,000+ spider species are dangerously venomous.  Today I’d like to highlight their valuable role as insect predators and point out a few reasonable precautions that should be taken when keeping spiders in captivity.

Hunting Methods and Diet

Spiders consume animals ranging from mites to birds.   Not all ensnare their prey in webs…some hunt by running (wolf spiders), Misumena vatia with waspswimming (European diving bell spider), spitting silk (spitting spider), hiding in flowers (crab spider), throwing webs (bolas spider), luring fishes while floating (fishing spiders) or rushing from burrows fitted with hinged doors (trap door spider).

However, all spiders consume insects, including agricultural pests and disease-bearing species, to some degree.  Field research has shown that harmful flies comprising over 60% of the diet of certain web-building species.  It is estimated that the weight of the insects consumed yearly by spiders in New Zealand exceeds that of the island’s human population!

Precautions – Bites and Urticating Hairs

The fact that so few spiders are dangerous to people should not be taken as a license to ignore caution when dealing with them. Just as with bees and other venomous animals, allergic persons can be injured or killed by the bites of relatively benign species, and potentially fatal infections can be associated with the bite of any animal.

Also, many tarantulas shed urticating (irritating) hairs when disturbed or even when just moving about. A colleague of mine underwent major surgery to remove such hairs, deposited on his hand by a “tame” red-kneed tarantula, from his eye.

That being said, I have kept native and exotic spiders since childhood, and have never been bitten – because I do not pick up spiders with my hands.  I urge you to handle spiders, if at all, with plastic tongs or by ushering them into a container.

Further Reading

The diving bell spider is certainly one of the world’s most interesting invertebrates – living within a submerged shelter that exchanges oxygen with the surrounding water and swimming after small fishes!  To read more, click here.

 

Misumena vatia with wasp image referenced from wikipedia and originally posted by Olei.

Wild Caught Invertebrates as Reptile and Amphibian Food – Pesticide Concerns – Part 2

Please see Part I of this article for a general discussion regarding the collection of insects and other invertebrates and their use in the diets of captive reptiles, amphibians, birds, invertebrates and fishes. Today I’d like to focus on some areas of special concern.

Toxic and Biting/Stinging Invertebrates

Black WidowWhile not involving pesticides per se, for your own safety and that of your collection it is imperative that you learn to identify the toxic or otherwise dangerous invertebrates that you may encounter while collecting. A good field guide (i.e. Audubon, Golden Guide or Peterson series) is indispensable in this regard. Be sure to handle unfamiliar species with plastic tongs.

Please bear in mind that even relatively mild bee venom can cause fatalities in allergic people. And while less than 1% of the world’s 40,000+ species of spiders are considered dangerously venomous to us, a number readily bite both people and animals in self defense. It is best, therefore, to avoid them…the Thin-legged Harvestman or “daddy long-legs”, which are not spiders, are safe to use. Steer clear also of bees, wasps, large ants, stag beetles and others well-equipped to defend themselves.

Bright colors often indicate that an animal is toxic or bad-tasting; ladybugs, fireflies, milkweed bugs and a great many others fall into this category. Unless you are sure of an insect’s identity, the safest course of action is to avoid brightly-colored species.

Native vs. Non-Native Prey Species

In many cases, predators avoid dangerous prey animals that occur naturally within their ranges; this can spare both pet and pet- Milkweed Bugskeeper a good deal of grief!  However, dangerous non-native prey animals may be attacked with abandon if the hunter has no “frame of reference”, so use extra caution in such cases.

I have, for example, housed highly-toxic Marine Toads with Green Anacondas for decades without incident, despite the fact that anacondas consume non-toxic frogs readily. However, Australian monitors and snakes, which have no instinctive or learned toad avoidance behavior, eagerly consume the Marine Toads that have been introduced there, often with fatal results.

Earthworms

Earthworms are one of the most nutritious live foods available. There are, however, situations that warrant precautions.

Earthworms are unique in consuming dirt as they tunnel, and in doing so may concentrate toxins present there. To my knowledge, the only problem that has arisen thus far has involved worms that dwell along golf courses, which are subjected to unusually high degrees of pesticide application. Please see my article Raising Earthworms for details concerning striped skunks and earthworms in NY.

West Nile Control and Related Programs

Avoid collecting invertebrates for 1 week after an area has been sprayed as part of West Nile eradication efforts, and steer clear of farms where pesticides are known to be applied regularly. Avoid also local insects that are considered to be agricultural pests, as they are likely the subject of control measures (this may apply to aphids, caterpillars, Japanese Beetles, etc.).

Enjoy

Despite the precautions that must be taken, invertebrate collecting is a fascinating and thoroughly enjoyable endeavor. Don’t forget to examine your catch closely…several years ago a new species of centipede was uncovered in NYC’s Central Park, on ground trod daily by thousands of people. Like me, you just may wind up keeping some of your discoveries in captivity for their own sake!

Further Reading

For a very interesting account of how toads learn to avoid stinging insects, please see my article Amphibian Learning Abilities.

Please write in with your questions and comments.

 

Black Widow image referenced from wikipedia and originally posted by Trachemys.

Milkweed Bugs image referenced from wikipedia and originally posted by Greg5030.

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