Mexican red-kneed bird-eating spider

Scientific name: Brachypelma smithi

Country: Mexico

Continent: North America

Diet: Insects - insectivore, small birds, small mammals, reptiles. In the Zoo they are given locusts and crickets. They only need to be fed once every two weeks. A dish of damp moss is supplied so they always have access to drinking water.

Food & feeding: Carnivore

Habitats: Desert & semi-desert

Conservation status: Near Threatened. It is the only tarantula on the CITES Appendix II list, which means its trade is only legal with captive-bred individuals.

Relatives: Black widow, imperial scorpion

Description: These are big spiders with a leg span of around 14 cm. They are covered in fine black hairs, with yellow and orange hairs around the knee joints. They have a total of eight small eyes, but despite this, their eyesight is believed to be poor.

Lifestyle: This spider is frequently found on hillsides or banks of earth. Burrows are excavated in soft earth or natural crevices under rocks or tree roots. The burrow entrance is large, vertical and irregular, shaded and obscured by plant debris.

Family & friends: Bird-eating spiders are territorial, living in their burrows by themselves.

Keeping in touch: Little is known about how these spiders communicate during the breeding season.

Growing up: Little is known about breeding in the wild. In captivity, the male is mature at about five years and the female at about seven years. Around two weeks after his maturing moult, the male produces a sperm web to transfer the sperm to his palps (two smaller leg-like appendages near his fangs) ready for mating. He advances towards a female and if accepted by her, holds her fangs while transferring sperm. One to two months later she produces an egg sac, a large ball of silk containing up to 1000 eggs. The spiderlings hatch and moult once in the egg sac. They emerge after two to three months. The young grow slowly and moult about once a month for the first six months and then at longer intervals.

These spiders are only mildly poisonous to man, but their large fangs can inflict a deep wound. The hairs are shed, particularly if the animal is disturbed, and can cause an allergic reaction.

Conservation news: The species is classified as 'Low Risk: Near Threatened', but this is largely due to not enough information on the species. The increase in the collection of the species from the wild for use as pets, and the subsequent fall in numbers, may cause the species to be re-categorised as 'Threatened'.