(The pictures up above include a number of other cacti besides the easy to identify Saguaro cactus)

There’s no way to ignore the ecology of each of the National Parks, and that is especially the case in the parks that are located in the deserts. These environments are challenging to say the least, as water is at a premium and that limits the amount of the photosynthetic primary producers, namely the plants, who can survive here. Even now in January, the temps are in the 90’s, the sun is relentless, and the ground is dry as a bone. Plants here survive by storing water when the rains come during the winter and spring and preventing it from evaporating from the plants during the long, hot, and dry summer and fall seasons. Most plants keep the water inside their cells using two methods. First is that the outside of the plant usually consists of a thick and waxy covering that protects it from the heat and prevents the water from evaporating. It also stores the water as a gelatinous substance that also makes it difficult to evaporate. The second way is to usually cover themselves with thick and incredibly sharp spines that dissuade any animals from eating them for the water they contain. While there are numerous cacti and other plants to be found here, the park gets its name from the giant Saguaro Cacti that dominate the parks landscape. These cacti can grow up to 50 feet tall, weigh several thousand pounds, live up to 150 years, and can store up to 200 gallons of water that they soak up during the rainy season. Their trunks and arms have pleats in them that allow them to expand when taking in and storing water. These cacti provide the perfect location for nesting birds who eat a hole into the cactus and build their nests inside. The sharp spines on the outside of the cactus prevents predators from climbing up and reaching them. The perfect protected fortress. Birds that utilize the cactus for this purpose include woodpeckers, kestrels, wrens, Lucy’s warblers, kingbirds, owls, Harris hawks, and martins. In addition to providing nesting locations, birds and other animals also eat the nutritious fruits and seeds that the cactus produces during the spring and summer. In addition to birds you’ll also find honey bees making nests in the cacti including killer bee’s. You’ll find a great variety of other animals that make the desert their home including rattlesnakes, quail, desert tortoises, reptiles like the Gila Monster, rabbits, coyotes, Javalina’s (from the peccarie family), rodents like the kangaroo rat, and mountain lions. Many of these animals are nocturnal, avoiding the searing daytime temperatures in favor of the cooler evenings. All of these animals depend in some way on the deserts plants for both food and for water.

Some Saguaro’s will die of old age but others succumb to freezing temperatures in the winter, lightening strikes, drought, strong winds, and destruction from grazing animals that all take their toll on the cactus forests.

They are truly magnificent organisms to stand next to where you can truly appreciate their immensity, and their long lives is a testament to how well they are adapted to this harsh environment. They are a site to behold and their survival in this environment is truly something to marvel at.