Red-tailed Hawks begin migration north, though some remain in the area and begin building nests and laying eggs this month. Photo by Ty Fitzmorris.
By Ty Fitzmorris
In most years, February in the Central Highlands of Arizona is still a very quiet time when mammals, birds, reptiles, insects and plants remain quiescent, waiting for the combined cues of increased day length and higher temperatures to end their winter diapause and begin searching for mates and food. But, in all years, the first glimmerings of spring’s vivacity begin this month in the deserts and the chaparral of our region. Over the next several months the activity in the lowlands grows from a hum to a roar, and gradually flows up the slopes and into the highest mountains carpeting the whole of the Central Highlands with flowers, warblers, and butterflies. But, for now, the uplands remain relatively quiet, leaving the naturalist to search for hints of spring.
Bird migrations begin to pick up steam, as overwintering species such as Northern Goshawk and Townsend’s Solitaire begin the months-long journey that will ultimately end in their breeding grounds as far north as the Arctic Circle. Other species migrate through the region to points nearer to the north, while the last of the migrants include the neotropical migrant warblers, who have spent the winter in the rain forests and dry forests of Central America and will breed and nest here. The overwintering waterfowl on Willow and Watson lakes, as well as the many smaller bodies of water will stay in our region for a while yet since they need to wait for the lakes to the north to thaw before migrating.
A very small number of insects and their relatives begin to wake from their short winter torpor in February. On sunny days Mourning Cloak Butterflies (Nymphalis antiopa) begin claiming mating territories in river bottoms, and can be seen patrolling in lazy circles, chasing passersby. The earliest flowers, such as some manzanitas and willows, draw honeybees as well as native bees, which are extremely variable in size and color. Small longhorn bees, iridescent mason bees, and early bumblebee queens can all be seen at these blooms during sunny spells.
Most remarkable, however, is a phenomenon that is barely noticeable — astute observers will see a proliferation of spider silk blowing in the sunlight, and near cliffs and canyons these pieces of silk might be extremely abundant, lofting in the wind. These pieces of silk are actually “balloons” created by young spiders, who use them to catch upward breezes and disperse over vast distances. In fact, many will loft up to a thin band of the atmosphere called the Aeolian Zone, which wavers around 25,000 feet in altitude. This largely unstudied region is populated by pollen grains, fungal spores, and very small insects, all of which might be able to cross vast distances once they’ve reached this relatively stable atmospheric zone.
February can bring amazing storms and holds the record for both the most snowfall in a month and the highest rainfall in a 24-hour period. On the other hand, February’s precipitation is extremely variable and difficult to predict, with as many as one in ten years receiving no or nearly no rain or snow. A wet February can, by itself, usher in a glorious, flowering spring, while a dry one when there is no other snowpack can herald low fuel-moisture and high fire danger. In high desert such as the Central Highlands, the abundance and distribution of water is the single greatest predictor of all activity in the wilds.
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White-tailed Kites are extremely rare vagrants in the region, but this one, which visited Willow Lake in February of 2014, found abundant prey. Photo by Ty Fitzmorris.
A Very Brief Survey of What’s Happening in the Wilds
High mountains
• Ravens begin nesting and laying eggs. Yearling Ravens have spent the winter in communal roosts and can be seen flying in large numbers, but these flocks begin to break up now as breeding pairs form.
• Northern alpine birds, including Red Crossbills and Pine Siskins, move into this area during extreme cold to the north. These finches follow the seed crop of coniferous trees, including Douglas Fir, White Fir, spruces, and pines.
Visit: Maverick Mountain Trail, No. 65.
Ponderosa Pine forests
• Peregrine Falcons return to our area from the south to reoccupy nest sites. Most Peregrines are monogamous from year to year, with both partners migrating independently back to previous nest sites and beginning courting and mating once there. This species is named for its extraordinary migrations, which can lead some individuals to migrate from Chile to Greenland.
• Abert’s Squirrels chew off the tips of growing Ponderosa branches to reach the inner bark, or cambium. This is an important food source for this rare squirrel during the late winter after they have depleted their other food stores, but they are also performing a vital service to Ponderosas. Ponderosas rely on a symbiotic root fungus to break down soil nutrients, and Abert’s Squirrels carry this fungus in their feces, transporting its spores from tree to tree and thereby keeping forests healthy.
Visit: Miller Creek Trail, No. 367.
Pine-Oak woodlands
• Townsend’s Solitaires, relatives of the American Robin, begin migrating north to their breeding grounds as far north as Alaska. Solitaires subsist largely on the last of juniper berries from last year’s crop while in their wintering ground.
• Sharp-shinned Hawks, the smaller cousin of the Cooper’s Hawk, begin migrating north through the Central Highlands. These small hawks were once considered a threat to songbird populations, and so were hunted aggressively. Now “mesopredators” such as the Sharp-shinned Hawk are understood to foster biodiversity by preventing one species from outcompeting another, and studies have documented increases in prey species where these types of predators are found.
Visit: Little Granite Mountain, No. 37.
Pinyon-Juniper woodlands
• One-seed, Utah, and Rocky Mountain Juniper release their pollen now, causing extraordinary allergies for many mammal species.
• Winter flocks of Western Scrub Jays begin to break up as jays form breeding pairs.
Visit: Tin Trough Trail, No. 308.
Grasslands
• Pronghorn begin giving birth after eight months of pregnancy. Young Pronghorn are able to walk after only about an hour and can outrun a human when they are several days old. Pronghorn typically give birth to twins who will remain in the center of their herd for several months.
• Toward the end of the month, broad-winged hawks such as the Rough-legged Hawk, Ferruginous Hawk and Swainson’s Hawk begin migrating north through the Central Highlands following the open grasslands where they can see rodents. Many can be seen perching on power line posts during this time.
Visit: Mint Wash Trail, No. 345.
Riparian areas
• Beavers, after consuming most of their winter stores, are very active in chewing away the inner bark of riparian trees. Their breeding season continues.
• Coyote Willow (Salix exigua) flowers and is mobbed by Honeybees (Apis mellifera) for nectar and pollen. Honeybees are native to Europe and are unlike most of our native bees in that they are social and live in massive hives of up to 80,000 individuals. North America is home to roughly 4,000 species of native bees, most of whom are either solitary or seasonally social, and so remain inactive during the winter.
• Newborn River Otters remain in their dens and, toward the end of the month, open their eyes for the first time.
• “Vagrant” bird species (birds dramatically outside their range) can be found in and around the region’s lakes. Some of these birds have been blown by storms, while others are simply exploring potential habitat. These might include Common Loon, Ross’s Goose, Tundra Swan, and extremely rare species such as the White-tailed Kite.
• The first migratory songbirds, including spectacular breeding-plumage warblers, follow rivers and riparian corridors through the region to their breeding territories to the north.
Visit: Willow Lake Loop Trail, off of Willow Creek Road in Prescott.
Deserts/Chaparral
• Flowering begins in earnest, starting with Brittlebush (Encelia farinosa), which paints large swaths of the desert bright yellow. Some species of verbenas and anemones, as well as Desert Marigolds (Baileya multiradiata), begin flowering at lower densities. In some pockets, manzanitas begin flowering.
• Butterflies begin flying, including the small Sara Orangetip (Anthocaris sara) and the tiny Spring Azure (Celastrina ladon), both of which can be seen at patches of wet mud, seeking out minerals and nutrients.
Visit: Agua Fria National Monument.
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February Prescott Weather
Average high temperature: 54 F, +/-4.3
Average low temperature: 23.9 F, +/-3.7
Record high temperature: 77 F, Feb. 2, 1986
Record low temperature: -12 F, Feb. 6, 1899
Average precipitation: 1.77”, +/-1.76”
Record high precipitation: 10.59”, 1927
Record high snowfall: 37.5”, 1932
Record low precipitation: 0”, 7.1 percent of years on record
Max daily precipitation: 7.92”, Feb. 28, 1905
Source: Western Regional Climate Center
Skyward
• Feb. 3: Full Moon at 4:09 p.m.
• Feb. 6: Jupiter at Opposition. The largest planet in our solar system, a gas giant, is at its closest to Earth and is fully illuminated. This is the best time to view Jupiter, and binoculars or medium-sized telescopes will reveal as many as four bright moons scattered in a line around the planet, and often the red storm-band around the planet’s center.
• Feb. 18: New Moon at 4:47 p.m.
• Feb. 21: Conjunction of Waxing Moon, Venus & Mars. The 3-day-old Moon will be within about two degrees of Venus and Mars, the Earth’s nearest planetary neighbors, low in the west just after sunset.
• Feb. 22: Conjunction of Venus and Mars. This extremely close encounter (roughly half a degree) between Venus and Mars will be visible to the west after sunset. Venus is the second brightest object in the night sky, so look for the brightest thing visible when few stars are out.
• Astronomical Highlight: When the skies are at their darkest early this month, our nearest galactic neighbor, the Andromeda Galaxy, is visible with the unaided eye. Look for the galaxy as a smear of light next to Andromeda’s knee, to the northwest after twilight, or using a more direct method, draw a line between the two highest stars in Cassiopeia — Segin and Ruchbah — and the brightest star in Andromeda, Alpheratz (her head in most drawings), and then look for the galaxy two-thirds of the way from Ruchbah to Alpheratz. The Andromeda Galaxy, which is the furthest object that can be seen with the naked eye, at 2.5 million light years away, is very slowly headed our way, and will collide with our galaxy, the Milky Way, in 5 billion years, after our sun has turned into a red giant and consumed the Earth.
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Ty Fitzmorris is an itinerant and often distractible naturalist who lives in Prescott and is proprietor of the Peregrine Book Company, Raven Café, Gray Dog Guitars, and is a founder of Milagro Arts, a community arts nexus, all as a sideline to his natural history pursuits. He is also the curator of insects at the new Natural History Institute at Prescott College. Contact him at Ty@PeregrineBookCompany.Com with questions or comments.