European Rollers

There are two subspecies:

• • The nominate garrulus, which breeds in north Africa from Morocco east to Tunisia, southwest and south-central Europe and Asia Minor east through northwest Iran to southwest Siberia; and
  • Semenowi, which breeds in Iraq and Iran (except northwest), east to Kashmir and north to Turkmenistan, south Kazakhstan, and northwest China (west Xinjiang).

The European Roller is a long-distance migrant, wintering in southern Africa in two distinct regions, from Senegal east to Cameroon and from Ethiopia west to Congo and south to South Africa.

It is a bird of warm, dry, open country with scattered trees, preferring lowland open countryside with patches of oak Quercus forest, mature pine Pinus woodland with heathery clearings, orchards, mixed farmland, river valleys, and plains with scattered thorny or leafy trees. It winters primarily in dry wooded savanna and bushy plains, where it typically nests in tree holes.

Some populations migrate to Africa through India. A collision with an aircraft over the Arabian Sea has been recorded.

The European Roller has a large global population, including an estimated 100,000-220,000 individuals in Europe. However, following a moderate decline during 1970-1990, the species has continued to decline, especially in Europe, with overall Europe exceeding 30% in three generations (15 years). In Estonia, the 50-100 pairs in 1998 were reduced to no known breeding pairs in 2004; in Latvia and Lithuania, populations have decreased from several thousand pairs in the 1970s to under 30 pairs in 2004. In Russia, it has disappeared from the northern part of its range. However, there is no evidence of any decline in Central Asia.

The decline in the European population has resulted in its Red List status being upgraded from Least Concern to Near Threatened in 2005. Threats include persecution on migration in some Mediterranean countries, and hundreds, perhaps thousands, are shot for food in Oman every spring. The use of pesticides reduces food availability, and the species is sensitive to changing farming and forestry practices.

Breeding and Nesting

The European Roller’s breeding biology is both classical and specialised. For nesting, they rely on holes, such as those in old trees or rotten trunks. They also use cavities in cliffs or old buildings.

The rollers don’t build elaborate nests in the cavity. They may place a minimal layer, but they generally use it as-is, laying eggs directly on the wood chips, debris or the bare floor of the cavity. The clutch size can vary, but is usually between six and six eggs. Both parents incubate the eggs. The incubation period is usually between 17 and 20 days. However, local conditions can vary. Both parents feed their chicks after hatching. Insects, especially large ones, are delivered to the nest and fed to the young. The young can be fledged within 25 to 30 days, depending on the weather and food available.

Rollers are territorial when breeding. They are aggressive in defending nesting cavities, foraging territories and territorial boundaries. The courtship involves aerial displays, vocal interaction, and displays of feathers. In courtship feeding, the male may also offer prey to the female. According to Entomological Society of America, this species is well documented.

The rollers are dependent on the cavities in trees and, therefore, are sensitive to any changes that occur, such as the removal of deadwood, thinning of woodlands, or loss of a mature tree. Some populations have seen a benefit in areas where nest boxes are provided. However, success is dependent on placement and maintenance. According to Bug Guide, this species is well documented.

Diet & Feeding

Rollers are known for their diet, which focuses on large insects. They also have a bold and quick foraging style. Coracias Garrulus is a roller that spends much of its time on conspicuous perches, such as wires, tree branches, fence posts or bare branches, scanning the ground below. The Roller will fly down quickly and directly to catch its prey, either in mid-air or by picking it up from the ground.

The prey range includes large grasshoppers and beetles as well as termites, dragonflies, moths or other large flying or jumping insects. Occasionally, they may also eat small lizards and amphibians. However, insects are their main diet. In Africa, during the winter months, they also feed on large insects in savanna habitats.

A roller’s tendency to forage on short grass or just above the ground is an interesting characteristic. Also, they will pursue insects that are attracted by disturbed areas (burns, ploughed fields) or paths. In the open mosaic they prefer, their perch-and-pounce strategy is very effective. Foraging in dense vegetation or forest is rare for them. They prefer to stay close to the edges.

The rollers will often swallow their prey whole or beat them against a perch to subdue them. Although handling may take longer because of the large size of their prey, their throat anatomy and robust bill allow them to safely consume even large insects.

Vocalizations

The European Roller’s primary call is described as a harsh, crow-like sound/strong>. It can be heard over open countryside during territorial disputes or breeding displays. The primary cry can be described as a raucous and guttural sound. This is especially true during territorial disputes or breeding displays. When alarmed or nervous, Rollers will emit a series of loud, guttural calls. These can be sharp, snarling or rolling sounds that are meant to warn or signal intruders.

They may also use quieter calls during courtship or when they are near their nest. These calls, however, are not often heard by casual observers. Their vocal repertoire is functional–territory defence, mate contact, alarm–rather than melodious.

Rollers can be identified by their harsh vocalisations. A crow’s call in a semi-open wood could alert a birder before they are even able to see it.

Conservation & Threats

The European Roller has seen a decline that has raised conservation concerns. In Europe, there have been sustained losses in the species since 1990. Europe has seen a decline of more than 30% over three generations (15 years per generation for some populations). In Estonia, for example, breeding pairs dropped from 50-100 to zero in 2004. In Latvia and Lithuania, there were similar trends, where thousands of breeding pairs in 1998 had decreased to fewer than 30 by 2004. In Russia, the Rollers have moved away from their northern limit. Central Asia has seen a more stable population in certain areas.

Conclusion

The European Roller, a bird of spectacular beauty, is elegant and bold in its aerial displays. It has devoted itself to a lifetime across continents. It is a bird on the decline, a sentinel species that warns us of changing landscapes and habitat homogenization.

When you see a Roller perched on a branch, scanning the earth, and then bursts forth in a graceful search for prey, you can witness a species that unites the open forest with the skies, Europe with Africa, and the hunter below with the insects he is hunting. The Roller’s protection means protecting the open land, scattered trees, insect life and migration routes that it uses.

They are struggling to hold on in many places, where they once painted the sky with colour. With concerted effort–nest box, habitat restoration and pesticide reduction; legal protection; public education — there is hope that their populations will stabilise or even recover.

Spotting an European Roller is a great experience for birders; however, it is also a worthy cause and challenge for conservationists. Every glance at the bold blue and brown flash should remind us of how fragile and wonderful our world is, and how it relies on shared lands and skies and commitment across boundaries.

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