Arizona Upland/Eastern Sonoran Basins

Sonoran Desert Tortoises (Gopherus morafkai) have been out on the ground across the Tucson basin from mid-August into the second week of September, most of them in the Avra Valley west of the city and a smaller set on the rocky slopes below the Catalinas. This is the one stretch of the year when the odds of meeting one on a trail are good. The animal spends most of its life underground or under rock, and it comes out mainly in daylight during the monsoon, when the rain has greened up the forage and filled the shallow pools it drinks from.It is a domed, high-backed tortoise the color of the caliche it digs into, with a shell somewhat narrower and more pear-shaped than the Mojave desert tortoise's. The two species are split by the Colorado River and do not overlap here, so any wild tortoise on this side of the river is the Sonoran one. It favors steep, rocky ground and the bajadas below it, not open valley floor, and it shelters in burrows it digs itself, in caliche caves, and in rock crevices.The tortoise drinks from puddles a finger deep by putting its nostrils to the surface and pulsing its throat to pull the water in. It also scrapes basins in the soil to catch rain and remembers where they are, walking directly to them when a storm passes. What it takes in goes into a bladder that can hold water for extended periods and release it back into the bloodstream as the body needs it. When a rain finally comes after a long dry spell, a tortoise drinks heavily, voids the concentrated urine it has been carrying, and stores fresh water in its place. In a hard drought an adult can go a long time without drinking.It eats plants only, leaning on annual wildflowers first and then grasses and cactus, with prickly pear fruit taken whenever it is ripe. September is also hatching season. Eggs laid in early summer, buried in the floor of burrows, hatch in September and October, though some clutches hold over and hatch in spring. A hatchling is about the size of a silver dollar and soft-shelled for years. Only a small fraction reach adulthood. Those that do mature between 13 and 20 years old and can live 50 to 80 years, which means a tortoise crossing a trail this week may have been crossing the same slope since before the surrounding subdivisions were built. Breeding peaks in August and September as well, so two adults seen together right now are likely a courting pair.iNaturalist flags the species as threatened, but the U.S. Fish and Wildlife Service reviewed it and found in 2022 that federal listing was not warranted, and it does not appear on the current federal list for this area. The pressures on it are the same either way. Buffelgrass, an introduced African grass now widespread around Tucson, burns hot enough to kill saguaros and palo verdes on slopes that never evolved with fire. The tortoise needs an unburned desertscrub slope with rock to hide in and annuals to eat after rain.Anyone who finds one should leave it where it is. A tortoise picked up or frightened may void its bladder, and in a dry year that is the water it was counting on to get through to the next storm.

A Short-tailed Hawk has held its ground on Mt. Bigelow Road for the better part of two weeks, with 71 separate confirmed reports and repeat sightings of two birds together as recently as August 27. The persistence is the real story. This is a species built around Florida and the humid tropics, with only a scattered foothold in south Texas; a single bird passing through the sky islands of southeastern Arizona would already be notable, but a pair lingering through late summer, the peak of the breeding window, raises the question of whether something more than passage is underway.Short-tailed Hawks hunt on the wing, soaring high over forest edges and dropping suddenly on birds below, a technique that has earned them comparisons to a falcon more than a typical buteo. Nesting requires mature stands with tall trees, and this stretch of the Catalina Highway corridor still supplies that structure as it climbs from desert floor into pine-oak and mixed conifer forest. The land underneath is federal. PAD-US puts the corridor inside Coronado National Forest, and records a Catalina Highway Scenic Area unit — 15,537 acres in total extent, managed by the Forest Service — at GAP status 3: protected from outright conversion, but still open to extraction such as logging, grazing or mining. The surrounding national forest carries the same status. That is a step below the GAP 1 wilderness units a short distance away, Pusch Ridge and Rincon Mountain among them, where land is managed for biodiversity and natural disturbance is allowed to run its course. For a raptor that depends on old, standing timber, which management regime governs the trees it is using matters as much as whether the trees are there at all.The species' nesting habits are poorly documented even within its core range, which makes this sighting more than a checklist entry. Whether this pair is simply lingering or actually attempting to nest is a question worth watching carefully over the coming weeks, ideally from a distance that leaves the birds undisturbed.

The monsoon has flipped a switch for the Sonoran Desert Toad (Incilius alvarius). Across the Tucson basin and washes from Cactus Forest Drive to Madera Canyon, Box Canyon Road, and Sonoita, observers have logged 49 sightings of this heavy-bodied toad in the past 30 days, following eight months of near total absence, with only two stray records between last October and this May.A similar pattern, near-silence followed by a sharp midsummer cluster, appears in last year's iNaturalist records too, though these are community-science observations shaped by observer effort as much as by the toad's actual movements, so it's worth treating as a suggestive signal rather than a confirmed recurring trend. What is well established is the biology behind it: this is North America's largest native toad, a stocky, warty animal that can reach over seven inches long, and it spends most of the year buried underground in a state of dormancy, waiting out the dry heat. It surfaces almost entirely in response to soil saturation from monsoon rains, emerging to breed in temporary rain pools that may hold water for only a few weeks. Eggs and tadpoles have to develop fast in that narrow window; miss it, and there is no second chance until the following summer.The species is also listed as threatened on iNaturalist, which makes this brief, rain-triggered burst of activity worth watching closely while it lasts, rather than something to assume will repeat on the same schedule every year. A poor monsoon, or pools that dry too quickly, can mean a season with no successful breeding at all for a toad that already spends the other eleven months of the year out of sight.

Pima County's drought picture has changed dramatically at one end of the scale and barely at all at the other. This same week last summer, the entire county sat in severe drought or worse, with nearly forty percent of it classified as extreme. Since early December, that extreme category has held at zero, week after week, for almost eight months straight, a real and durable retreat at the top of the drought ladder.But severe drought itself hasn't followed the same trajectory. That broader category has been stuck flat at just over forty percent of the county for eight consecutive weeks now, even as the extreme tier stayed clear. It amounts to recovery at the ceiling without recovery in the middle, and it's a useful corrective to how a single dramatic event can read on the ground.Desert vegetation and groundwater don't work on a single-storm timescale, though. Saguaro, palo verde, and the region's aquifers track the cumulative, multi-year drought classification, not any one pulse of monsoon rain, however impressive in the moment. This is a classification comparison rather than a direct streamflow or groundwater reading, and it says the region has pulled back from the worst extreme without yet climbing out of the broader dry pattern underneath it, a distinction worth keeping in mind across this landscape's basins and uplands as the monsoon continues to unfold this season.

Apache cicadas (Diceroprocta apache) are at their singular ecological moment — nymph husks still clinging to paloverde bark, living adults screaming through the midday heat, and the first dead adults turning up on the ground, all within the same week. This compressed overlap is the signature of a species whose adult life is brutally short: years spent underground as a nymph, then a few weeks above ground to mate and die before the monsoon rains fully saturate the soil.What makes the Apache cicada remarkable is not just the brevity of emergence but its choice of stage: it is one of the few animals on earth that actively sings during the hottest hours of the hottest days, performing above 105°F when every other creature has retreated to shade — a physiological extreme that researchers are still working to fully explain. The O'odham recognized this chorus as a calendar marker for generations: when the cicadas are loudest, the desert is at its thermal peak and the rains are either coming or already here. Right now, both are true.

The monsoon arrived this week in a single violent pulse: the stream crested near 25 feet, then drained to bare sand within hours. That violent pulse-and-retreat is the desert's ecological signature, and it triggers a cascading response in the creatures that depend on it.Flame Skimmers and Mexican Amberwings are now working the scattered pools left behind, patrolling intently for breeding sites that may persist only days before evaporating entirely. The dragonflies know the window is impossibly narrow — in the Sonoran Desert, temporary water is the only water most years. Marl Pennants have also appeared at the same pools, all three species responding to the same hydrological signal.On the banks, velvet mesquite is in full flower and pollen release, with ripe fruits already visible — a compressed phenological rush to capitalize on moisture and the brief window of insect activity. This is the desert's second spring, born from water that appears and vanishes in a matter of hours.

Fishhook barrel cacti are in flower as of July 5, arriving just as the washes drop to zero flow. The bloom is timed to precision: a biological barometer that draws native bees in the days before the monsoon arrives.The O'odham people recognized this threshold as its own season, marking the shift between the dry months and the summer rains. The desert blooms by the same calendar they did—a reminder that the most reliable instruments for reading this landscape have always been the plants that live here.

Saguaro fruits split open this week across the bajadas and canyon floors — their red crowns signaling a transition in the desert cycle that has shaped human and animal life here for centuries. Doves and bats move through the stands now, drawn as much by the pulp's water content as by the calories; in a landscape where washes have stopped flowing, the fruit itself becomes a seasonal water source.The Tohono O'odham marked this ripening as the beginning of their year, brewing the harvest into wine used in ceremonies to call the rain. Ecology and culture intertwined: the abundance of ripe saguaro fruit marked when the monsoon season was near, when the dry washes might finally run again. An Apache cicada began calling yesterday — another phenological thread in the same arriving warmth.

Couch's Spadefoot toads (Scaphiopus couchii) emerged in a group of five on the evening of June 17, their sudden appearance triggered by the first heavy rain after months of burial underground. The wash channel ran dry all season — the desert willows nearby are just now opening their flowers. These signs mark the edge of monsoon arrival, when the summer rains finally break the heat.Couch's Spadefoots are among the desert's most precise rain sensors. Sealed in the soil for up to eleven months in a state near dormancy, they respond within hours to the right combination of rainfall and temperature, timing their emergence to exploit the brief window when temporary pools form and insect life explodes. A single cohort like this one is a reliable field signal that the atmospheric pattern has shifted.

Along the dry washes and canyon edges near Tucson, the desert willow is in full bloom right now. Its flowers are large and trumpet-shaped, pink to lavender with yellow streaking inside the throat, and they open in flushes through the longest days of summer. The tree itself is not a true willow — it belongs to a different family entirely, one more closely related to catalpa — but it grows where willows often do, in the sandy beds of intermittent streams where water moves underground even when the surface is dry. In this heat, with the air shimmering off bare gravel, the flowers are one of the more reliable nectar sources in the landscape.Queen butterflies are working those flowers right now. They are large and richly colored, deep mahogany-orange with black borders and small white spots along the wing edges. If you are near any flowering desert willow, watch for them — they move deliberately from bloom to bloom, hovering briefly before landing and extending their proboscis into the flower tube. The queen is closely related to the monarch, similar enough in appearance that the two are sometimes confused, but the queen's wings lack the monarch's bold black veining across the orange field. Queens are year-round residents in the Sonoran Desert, not migrants, and summer is their breeding peak. The adults feeding now are building the energy reserves that will support egg-laying through the hottest weeks of the year.The desert willow's flower shape is not incidental to this relationship. The trumpet is wide enough to admit a large butterfly, and the yellow-streaked interior guides visitors toward the nectaries at the base of the tube. When a queen lands and pushes its head into the flower, it contacts the anthers and picks up pollen on its body. Queens visit many flowers in sequence, and that movement carries pollen between individual trees. Desert willow depends heavily on large pollinators — hummingbirds work the same flowers, and black-chinned hummingbirds are present in this area now — but butterflies like the queen are consistent visitors through the summer months when hummingbird activity can be less predictable. The tree blooms repeatedly through summer, producing new flower clusters as old ones drop, which keeps the relationship active for weeks rather than days.Queens also have a relationship with a different set of plants entirely, and it runs parallel to the pollination story without overlapping it. The caterpillars feed on milkweeds, and the adults seek out milkweed and related plants not just to lay eggs but to obtain alkaloids called pyrrolizidines, which the butterflies sequester in their bodies. Males use these compounds in courtship; the chemicals signal something about the male's quality or persistence. This is separate from what is happening at the desert willow flowers, but it means the adult butterflies are navigating a landscape of multiple plant relationships simultaneously — nectaring here, seeking out milkweed there, all within the same summer afternoon.Creosote bush is also flowering nearby, its small yellow blooms open in the same heat. The Mediterranean mantis, an invasive species established in the Sonoran Desert, is present in this area and hunts among flowering vegetation, ambushing visiting insects including butterflies. It is worth knowing that not every visit to a flower ends in a successful departure. The queens that complete their rounds and move on are the ones building the next generation.The light this time of year comes down hard and direct at midday, and the desert willow's canopy, thin and feathery, does not cast much shade. The flowers show up clearly against that bright sky. If one is blooming near you, watch the flowers for a minute. The wings of a feeding queen open and close slowly while it drinks, the mahogany color catching the full sun.