Did You Know common ravens are so smart that they:
Decide who is a friend and who is an enemy
Give gifts to say thank you
Have the most vocalizations of any bird in North America
Play games to have fun
Teach new skills they learn to other ravens
The common raven was once a migratory bird flying from Canada to Mexico. Today, however, ravens in the Mojave Desert no longer need to migrate – the majority are year-round residents – and this has caused an imbalance in the ecosystem. Today, their population is 17 times as large as it was just 40 years ago.
HOW HAVE RAVEN POPULATIONS GROWN SO MUCH, AND SO QUICKLY?
HUMANS PROVIDE UNNATURAL SOURCES OF FOOD, WATER, SHELTER, AND OTHER RESOURCES
Ravens are excellent at finding and using the resources provided by humans; they no longer need to migrate to find food, water, and shelter!
These resources can be purposely provided (like putting out bird seed in your yard), or they can be unintentionally provided (such as water run-off from sprinklers). As we develop the desert, our cities, towns and rest stops become sources of human subsidies for ravens and other wildlife. Some examples include:
Trash/Waste = food source
Irrigation and runoff on streets = water source
Artificial lakes, ponds, and fountains = water source
Buildings, power poles, billboards = nesting sites/shelter
This means they nest more often, and more chicks are surviving. The end result is an explosive increase in the number of ravens living in the Mojave Desert.
ARE RAVENS NATIVE TO THE MOJAVE DESERT?
YES, BUT THEY ARE CONSIDERED NATIVE INVASIVE SPECIES.
Due to the explosion in their populations, the raven is now considered a native invasive species. This is a species naturally found in the ecosystem, but whose population far exceeds the natural/healthy levels for that ecosystem. This imbalance has negative impacts to the ecosystem and the species that live there.
WHAT NEGATIVE IMPACTS DO THE RAVENS HAVE?
RAVENS PREDATE ON MANY NATIVE SPECIES SUCH AS BURROWING OWLS, THE COACHELLA VALLEY FRINGED-TOED LIZARD AND THE DESERT TORTOISE.