Hey everyone, this is my third round of research for my question: "How has the Joshua tree and the yucca moth shaped the Mojave Desert?" Wow! Three weeks has gone by so quick! This round is altered a bit, I decided to look more at what animals are endangered/on the verge of extinction, and what is causing their extinction. Not so much what role they play in helping the environment.
The Mojave desert has a very fragile ecosystem, threatened by urbanization and development. Many animals are abandoning their habitats due to off-highway vehicles causing erosion, landslides degrading water quality, and noise disturbances (2). In addition, groundwater pumping, construction or roads, agricultural pollutants, construction of large residential tracts, and grazing of domestic animals are also affecting the wildlife in the desert (3).
"Extinct Species: a species which has vanished from existence." (3)
"Endangered Species: a species of plant or animal in danger of extinction throughout a significant portion of its range." (3)
"Native Species: a plant or animal that evolved or was transported to an area through natural means." (3)
"Threatened Species: a species present in its range but in danger because of a decline in numbers." (3)
"Exotic: not native, something that did not exist in the area before humans brought it from another place." (3)
The Endangered Species Act is the strongest law that is protecting wildlife and plants in the U.S. (1).
The animals and plants stated on this act from the Mojave Desert are: (C=Candidate, E=Endangered, T=Threatened, S=sensitive)
- Bear-paw poppy -C
- Foxtail Cactus -C
- Eureka valley evening primrose -E
- Panamint daisy -C
- Sticky buckwheat -C
- Amargosa southern pocket gopher -C
- Desert bighorn sheep -S
- Mountain lion -C
- Townsend's big eared bat -C
- Bald Eagle -T
- Californian brown pelican -E
- Least bell's vireo -E
- Mexican spotted owl -T
- Yuma clapper rail -E
- Coachella valley fringe-toed lizard -T
- Desert Tortoise -T
- Lowland leopard frog -C
- Bonytail chub -E
- Colorado squash -E
- Devil's hole pupfish -E
- Mohave tui chub -E
- Humpback chub -E
- Razorback sucker -E
Insects and Snails:
- Badwater snail -C
- Devil's hole warm springs riffle back -C
The main threat to the desert tortoises are off-road vehicles, that are destroying their burrows underground (4). This is a threat that is affecting their habitat. Habitat conversion is also a result of urban development, mining, waste disposal and road construction. Their habitat can also be modified further by military training, utility corridors, and livestock grazing. However, the real decrease in their population is due to predation, disease, and recreational killing (5). Specifically, the desert tortoise is threatened by raven predation. Because they are very slow animals, they can't hide as quickly when being hunted upon by predators. With more people travelling to the Mojave, more litter and garbage is being left behind, attracting the population of the ravens, who feed on baby tortoises (6). In addition, many former pet tortoises have been released into the wild this past decade, carrying a deadly bacterium affecting the wild tortoises. This upper respiratory tract disease is affecting the tortoise's respiratory system and causing many to die (6).
Ridiculously enough, people in the past have hunted for these creatures, which has threatened their population today (4,5). Furthermore, invasive and non-native plants are affecting the quality and quantity of plant foods available to the tortoise, taking a toll on the amount of nutrients it intakes daily (5).
Mexican Spotted Owl:
The Mexican spotted owl is threatened by the loss of old growth forests, causing habitat destruction, and starvation. As well, climate change is taking a toll on them as the region gets hotter and drier, making their success in building nests decrease since they rely on precipitation to help. Because they are also affected by barred owl enrichment, and great horned owl predation, this is resulting in low reproductive rates, and low juvenile survival rates (7,8).
Coachella Valley Fringe-toed Lizard:
This species is threatened by urban sprawl, agriculture, and off-road vehicles, affecting their habitat, and leaving them with less and less protective cover (9). As well, nonnative plants such as tamarisk, are securing once moving sand deposits. This is preventing the replenishing of blow sand that the lizard relies on (10).
My next round will be on:
- Climate change, environmental issues, and other threats that can or have challenged life and survival in the desert.
- How we are helping to preserve the desert and its species to fight against these problems.
Comments and suggestions always welcome!