In 1994 this fascinating creature, the Arroyo Southern Toad was unfortunetly added to the endangered species list. The primary reason for their dissapearence was the habiat HABITAT DESTRUCTION (the loss or alteration of areas that supports teh species). Upstream, when dams form, it destroys the slow flowing areas the toads need to breed. The Arroyo cannot survive in a reservoir. Since dams alter the amount and timing of water flow downstream it provides unsuitable conditions for the toad, because of changes in location and quality with their habitat.
Human are also another dangerous factor for the Arroyo. Humans channel many streams for flooding, therefore changing the timing and quantitiy of water flow, as well as ripping up the sides of the streams to construct concrete walls. All of this is very harmful to the Arroy, not only hurting their daily habitats but destroying their breeding grounds.
The introduction of exotic species into the Eastern United States, has also been very harmful to the Arroyo. Bullforgs, bullhead catfish, and bass are now invading the Arroyo's (along with many othe native species to these streams and reserviors) habitat, by competing with them for food, preying on them and possibly spreading foreign diseases (www.sdnhm.org).
Not only are changes to the Arroyo's stream and reservoir habitats effecting their decline, but upland habitats as well. All over Southern California, GOLF COURSES, MALLS, HOUSES, or even AGRICULTURAL areas can have negative impacts on these species. Reaching adulthood, the Arroyo ventures from its niche in the water, up to dry land where these human developments have ruined their chances of a healthy survival in a once suitable native habitat.
ROADS are another detramental fator in the decreasing Arroyo
population, both in streams and upland areas. Not only are toads run over
in cars in sometimes huge quantities, the vehicles leave large amounts of
nasty deposits, which ulimately runs off the roads into the Arroyo's habitat.
Just a small amount of silt or petroleum by product pollution can KILL arroyo
toad eggs and larvae, which are very sensative.
This small peaceful toad would be extremely
detremental to loose.