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Halloween Creatures – Orange Crabs, Ghost Frogs, Vampires, Goblins…

Gluvia dorsalisHerp and invertebrate enthusiasts are never at a loss for frightening, even “ghoulish” (to “regular” people) stories. With Halloween just around the corner, I’d like to highlight some creatures whose names or habits associate them with this holiday.  Some, such as Thailand’s fanged, bird-eating frog and the skin-feeding Caecilian, are relatively new discoveries.  I’ve taken the liberty of extending beyond our usual subjects to include a parrot-eating bat and the well-named Goblin Shark.

Halloween Crab, Gecarcinus quadratus

Bright orange color and brilliant “eye-spots” on a round carapace lend this crab a pumpkin-like appearance.  Highly terrestrial, it lives along forest edges from Mexico to southern South America, returning to the sea only to reproduce.  Studies have shown that Halloween Crabs recycle vast quantities of dead leaves, acting as the “earthworms” of their ecosystems.

I’ve kept Halloween Crabs in zoo exhibits for years, and couldn’t resist purchasing a few at a recent reptile expo.  They make interesting terrarium subjects, and often give up their nocturnal ways to forage by day.  Please post a comment below if you would like information on their care. Read More »

Crickets and Carotenoids – Study Examines Cricket Nutrient Levels

veggiesCaptive insect-eating reptiles and amphibians (and perhaps invertebrates) are often plagued by nutritional deficiencies. A highly-varied diet is a great way to ensure adequate nutrition, but most keepers have access to only a few feeder-insect species; gut-loading (providing nutritious diets to feeders) is helpful, but detailed studies are lacking. While touring several Japanese zoos a few years ago, I was intrigued by the number of cricket species being bred as herp food, and resolved to investigate the species and diets I saw in greater detail. A recent article in Zoo Biology (2011, V. 30), which provides insights into carotenoid supplementation in three different cricket species, has re-sparked my interest. I’ll summarize below.

Carotenoids

Carotenoids are pigments that occur in plants. Animals, as far as is known, cannot manufacture carotenoids but rather must obtain them through their diet.

Carotenoids benefit the immune system by acting as antioxidants, function in the reproductive and other systems, and are believed partially responsible for the health benefits enjoyed by people who regularly consume fruits and vegetables.  We know little of their role in reptile and amphibian health, but many zoo nutritionists believe them to be important. Read More »

“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-Safe Cricket and Roach Control for Reptile and Amphibian Owners

Camel CricketAlmost every zoo building in which I’ve worked was home to roach (2-3 species) and House Cricket populations.  In most, pesticide use was not an option. An older animal keeper whom I befriended let me in on his favorite insect pest control technique – the molasses trap.  He was content to let management wonder how he did such a good job so, out of respect for him, I did not share the secret until he retired. Then, for a time, molasses traps became standard in several zoo buildings. Molasses is also useful in outdoor traps, where it never fails to turn up a variety of interesting species. I’ll expand on that below as well.

Pesticide Problems

House Crickets, roaches and other escaped “feeder insects” can be problematic in private collections. In the damp basements favored by amphibian keepers, Spotted Camel Crickets (Ceuthophilus maculatus, please see photo) may also set up housekeeping. These unusual creatures are very interesting in their own right, and I’ve featured them, and a large African relative, in several exhibits. However, most folks find their size, appearance and jumping abilities quite unsettling (please see comments in the article linked below – insect fans will find them very interesting!). Read More »

Live Food Care – Reptile, Amphibian, Tarantula and Scorpion Diets

Poplar Hawk MothI’ve covered a number of less-commonly kept food animals in this care guide, along with pet trade staples.  Please consider as many as you can, as dietary variety is critical to the health of most pets.  The extra effort on your part will be very worthwhile…novel foods also inspire enthusiastic feeding responses, and may even stimulate reproduction.

There is an endless supply of useful live foods, so please post your ideas and observations.

Earthworms, Red Wigglers, Nightcrawlers (Lumbricus terrestris, others)

I’d like to see earthworms replace crickets as dietary staples for those species that accept them.  Highly nutritious, they are readily taken by most amphibians and turtles, some lizards, insectivorous snakes, and tarantulas.  Most reproduce rapidly when kept in a screen-covered plastic container with alternating layers of dead leaves and moist topsoil; they can also be stored under refrigeration.  Keep earthworms at 70 F or below if possible (certain species tolerate warmer temperatures). Read More »

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