General
The greater blue derp (Athene derpi ssp. caeruleus maior) is a small, deep blue owl found all over the world. Not much is known about this newly discovered species as sightings have been rare, but they have been found in flat open landscapes, like grasslands, rangelands, deserts, and other areas with low vegetation. They nest and roost in burrows, which they create themselves and inhabit their entire lives. Like most owls they are active at night, and mostly do their hunting during dusk and dawn (the blue hour), when their colouring gives them the best camouflage.
Living close to the ground, the greater blue derp has developed longer legs that enable it to sprint, as well as fly, when hunting. When threatened, the greater blue derp freezes in place, regardless of its current activity, even in mid-sprint or mid-flight. This mostly results in awkward poses that the greater blue derp can hold for many hours, until the threat passes. When caught in mid-flight, it can lead to injuries, though no fatalities have been recorded.
Description
Greater blue derps have bright yellow or oranges eyes, and usually have similar coloured legs. Their beaks are a lighter yellow, sometimes grey. They have prominent white tufted facial markings and upper chests. The tufts next to their eyes are lowered or raised during certain behaviours. Adults have dark blue wings, and spotted heads, with a variation of blue spotting on the abdomen. Juveniles lack the spotting, and are dark blue, almost black in appearance. They become lighter with age. Males and females are similar in size and appearance. The greater blue derp measures no more than 19 cm (7 in), with a 50 cm (19.6 in) wingspan. It weighs up to 140 g (5 oz).
Distribution and habitat
There have been sightings on most continents, though the greater blue derp seems to prefer warmer, dryer areas. Because of its reclusive nature, it is believed that distribution is wider than has been seen so far, though this has yet to be verified. Greater blue derps live alone, or in pairs, unless they are breeding.
Behaviour and ecology
This species can live up to 20 years in the wild. They nest and roost in burrows that they create themselves when they leave their parents’ burrow. When they find a mate, they make a new burrow where they will stay the rest of their lives. Sometimes juveniles leaving the nest will use an abandoned burrow, but partnered derps will always create a new burrow.
When threatened, the greater blue derp freezes in place, regardless of its current activity, even in mid-sprint or mid-flight. This mostly results in awkward poses that the greater blue derp can hold for many hours, until the threat passes. When caught in mid-flight, it can lead to injuries, though no fatalities have been recorded. This strategy seems ineffective, or even counterintuitive. There is reason to believe the awkward poses scare of predators, but more research has to be done to confirm this.
Breeding
Nesting season begins early April. Unpartnered derps will set out on foot, making widening circles around its burrow. When it encounters another derp it will firstly perceive it as a threat and freeze in place. Both derps will now stand unmoving for an indeterminate time. When the other is to their liking, they will slowly start moving, starting with the eyelids, and working down to the feet. If the other derp does not reciprocate, the derp wanders off and continues its circling. If the feeling is mutual, they will take off in flight to find a new spot to burrow. A greater blue derp has no sexual preference, and will mate for life
When two partnered derps are of dissimilar sexualities, the female will lay a clutch of eggs over two days, which can consist of 5 to 7 eggs. The eggs are mottled light blue, almost translucent. Both parents then on and off incubate the eggs for about 4 weeks, while the other parent hunts for the entire nest. After the eggs hatch, both parents feed the chicks. Chicks start to fly and leave the nest after four weeks, but don’t fully live on their own until they are one year old.
Food and feeding
The highly variable diet includes invertebrates and small vertebrates, which make up roughly one third and two thirds of the diet, respectively. Blue derps mainly eat large insects and small rodents. They will perch above the grass to spot movement, and then swoop in to catch their prey. In flat areas they can also take short sprints, mostly use to catch ground dwelling insects.
Status and conservation
The greater blue derp is listed as Not Evaluated on the IUCN Red List
