Resourceful hunters deserve respect

THERE SEEM to be plenty of spotted flycatchers around this year. These little brown birds, with streaked pale breasts and little spots on their heads, are summer visitors to our shores.

Spending the winter in southern Africa, they are among the last migrants to arrive here. They breed quite late in the year; when there are plenty of insects for their babies to eat. Although they like wooded gardens, they don’t attract attention to themselves and are often overlooked. The resourceful little hunters deserve to be better known.

Flycatchers earn their crust by preying on insects. Swallows and swifts fly around with wide-open gapes, scooping up their prey, like vacuum cleaners mopping up dust. It’s a catch-all, highly effective technique and the swallows have developed swept-back wings and long tails to make their aerial trawling more effective. Flycatchers do things differently. Precision hunters, they selectively target individual insects. A flycatcher will perch on a branch, waiting for a victim to come within range. Then the bird sallies forth, seizes the insect in the air, and returns with it to the perch. This calls for co-ordination and precision flying of the most advanced kind, a miniature version of the peregrine falcon ‘stooping’ on a flying pigeon. The farther away the insect is from the perch, the more difficult the catch; flycatcher sorties of up to 25 metres have been recorded. Hunting is easiest during the heat of the day, when most insects are on the wing but flycatchers can catch moths under street-lights at night. In optimum conditions, an insect is caught every 18 seconds or so.

Captured bees and wasps are beaten and rubbed against a branch to remove their stings. The hard indigestible parts of the prey are coughed up as pellets. Insects don’t fly much in wet weather and the flycatcher turns its attention to ground dwelling creatures, flying over tall grass, hovering briefly from time to time and dropping on its victims. Berries are eaten occasionally.

Most small songbirds produce two or three clutches in a season, laying 12 or 15 eggs in all. Spotted flycatchers, however, have a low reproductive rate. In Europe they generally have two clutches but, in Britain and Ireland, most pairs produce a single clutch of only four or five eggs. Quite tolerant of people, they allow the nest to be approached closely and don’t become too alarmed. In Britain and mainland Europe, the great spotted woodpeckers, which steal eggs and chicks, are mobbed fiercely.

Flycatcher babies are fed on large flies but ants bees and wasps also feature in the diet. The stings are usually removed by the adults before the young are fed but, sometimes, dead bees are offered with their stings still intact. Perhaps this helps to educate the babies about the dangers out there. On fledging day, the adults bring food but withhold it from the chicks, coaxing them out of the nest. Once they leave, normal service resumes. Studies by the Cambridge ornithologist NB Davies showed that baby flycatchers begin to feed themselves about ten days later. From then on, the parents only bring food when a youngster actively begs for it. The young chase after the parents who tend, increasingly, to withhold the food. This makes sound hunting sense; the flycatcher hunting method requires the birds to be dispersed. A bird will catch few insects if it competing with the rest of the family for every insect which flies by.

THERE ARE 115 species of flycatcher in the world but the spotted is the only one which breeds regularly in Ireland. Another species, the pied flycatcher, breeds in Britain but shows no inclination to set up shop here. This reluctance is a bit of a puzzle; pied flycatchers breed in Wales in habitat very similar to that found in parts of Ireland. Pieds visit us during the migration season but, for some unknown reason, they don’t stay to breed.

The pied flycatchers in Britain like to use nest boxes so, in 1983, Irish ornithologist, Shay Fagan, erected 120 boxes on oak trees in three areas of County Wicklow. Tits availed of the boxes for the first two years. Then two pairs of pied flycatchers nested. The eggs hatched in both nests and Shay ringed the babies. But disaster struck; the boxes were raided by a predator, possibly a stoat, and none of the babies survived.

Martin Bradley and Ian Irvine had a similar nestbox scheme in County Antrim. Pied flycatchers were seen there from time to time but none nested. Then, in June 1985, a female moved into one of the boxes. She laid five eggs, hatching four of them. One baby died but three chicks fledged successfully. The nests in Antrim and Wicklow that year were the first breeding records for the species in Ireland. Hopes were high that the pied flycatcher would become an established breeder. However, since 1985, there have been only a few half-hearted nesting attempts.

Perhaps Ireland’s traditional family values are to blame for this. Male pied flycatchers are notorious adulterers. Most pairs are monogamous for the season, but a significant percentage of husbands are two-timers. They can hold two, occasionally three, territories, sometimes separated by several hundred metres, with a female nesting in each. Nor is the female flycatcher a saint; when her husband’s back is turned she may flirt with neighbouring males. Of the chicks examined in one Swedish study, a quarter were not the offspring of their putative father.