Nightingales in November (23 page)

Despite laying well before the Robins, the Peregrines' lengthier incubation means that among those clutches laid around mid-March, the chicks should only now be entering their final stages of development before the egg tooth is
deployed. As the female is charged with carrying out most of the brooding, the male's role will still be to provide the lion's share of food to keep both parents-to-be well fed.

Certainly in the case of urban-nesting Peregrines, feral pigeons are the most common food items consumed throughout the year, but as spring develops, Peregrine expert Ed Drewitt has found some fascinating changes in their diet. By analysing feathers collected at well-known urban nest-sites, he's been able to identify a whole variety of spring migrants caught and killed such as Wheatears, Turtle Doves, Nightjars and even the occasional Corncrake. Confined to rural farming locations in north-west Scotland, the British breeding population of the shy and retiring Corncrake is thought not to number any more than 1,200 pairs and it's patently obvious that these urban Peregrines have no respect for rarity when catching this member of the rail family during its migration north. Many of these migrants would never normally have been associated with urban habitats, but thanks to the Peregrines' opportunistic abilities, we're now learning more about their migration routes. In many cases it seems these migrant birds are flying over some towns and cities, which they may be using effectively as way-markers en route to their summer residences elsewhere.

By mid-April, most Kingfisher and Lapwing pairs will be in full incubation mode. Protected by their tunnel fortress, predation levels of Kingfisher eggs are thought to be very low, but the clutch is still rarely left unattended for any length of time to ensure the eggs don't chill. One disadvantage of nesting in almost total darkness, however, is that if an egg becomes separated from the rest of the clutch, possibly when being turned, then the adults don't seem to notice, leaving it to a chilling fate. Unable to see the outside world, the sitting Kingfisher will also have to wait for a whistle from its partner to know when a changeover is due. Upon hearing the signal
that the coast is clear, the previously sitting bird will emerge blinking into the daylight, giving it an opportunity to stretch, take a toilet beak and even catch a fish or two before sitting duties recommence.

By contrast, as Lapwings nest out in the open, any changeover between parents is far more easily coordinated, and so any egg accidentally dislodged can quickly be brought back into the fold. The main problem Lapwings have during incubation is preventing their eggs being either accidentally trampled on by cattle, or predated by anything from Carrion Crows and Stoats to Foxes and Badgers. Adult Lapwings can often deter any livestock from encroaching too close to their clutch by flashing open their wings in front of the cattle, but determined predators require a more concerted and coordinated effort. Carrion Crows are considered serious predators of eggs and will be mobbed severely by both parents if they approach the nest. Any Lapwings that have bred as part of a larger colony will often be able to collectively muster an aerial bombardment, enabling them to more effectively drive the crows right out of the territory. Mammalian predators, however, are a potentially very serious proposition, as they're also capable of taking any unwary adults sitting on clutches. When faced with a Fox or Stoat, for example, the Lapwings' main reaction is to circle above the predator while calling, which not only keeps both adults safe but also warns other birds of their presence, in turn making the nest more difficult to locate. Despite these techniques, some clutches are inevitably predated and so the Lapwing's last line of defence is simply to quickly replace the lost eggs in a different nest.

Starting before the nest is finished, the female Blue Tit will proceed to lay an egg each morning until her clutch is
complete. The eggs are white, with tiny reddish or chestnut speckles which are more densely concentrated at the blunter end, and weigh in at around 0.5g. The clutch size can vary enormously, between 5 and 16 eggs, although for the highest numbers there is the suspicion that maybe more than one female is laying in the same nest. Even so, Blue Tits lay some of the largest clutches of any songbirds, which fits in with their ‘all your eggs in one basket' strategy. Younger females tend to lay smaller clutches, while those birds nesting in woodland often lay more eggs than those who have chosen farmland localities, who in turn will frequently have higher broods than any Blue Tits which plumped for a garden nest box. Despite gardens being incredibly important for keeping hungry birds fed during the cold winter months, when it comes to the breeding season, it seems that deciduous woodlands, with their huge spring concentrations of caterpillars, will always trump anything that any other habitat has to offer.

Late April

After around four weeks of constant incubation, the female Lapwing's hard work will finally pay off as her clutch begins to hatch. Using their strong neck muscles and egg tooth, the chicks will break out by both bracing themselves against the inside of the egg while tapping away from inside to crack the exterior. Once the Lapwing chicks have recovered from their efforts and dried out sufficiently, their already advanced state of development means they're able to run around and feed themselves almost immediately. The precocious chicks are delightful little creatures, with long blue-grey or pinkish-grey legs, a short dark bill and sandy-brown down, which is dotted and streaked black. They also have a very distinct white patch on the back of their neck, which stands out
when the chicks are running around and almost certainly enables their parents to easily keep track of them. However, the instant they feel threatened, or in response to their parents' alarm calls, they will crouch motionless with their legs drawn in and heads down in order to hide the white patch and melt into their surroundings. Not needed to find food for their young charges, the parents' role is both to lead them to the good feeding areas and guard them from any marauding predators eager for an easy meal.

A mosaic of habitats seems to suit the chicks best, with wet patches and short swards for feeding, while also comprising longer, more rank vegetation for concealment should danger appear. Ideally these good feeding areas will be present within the parents' territory, but if not, the adults will quickly corral their offspring away to other locations, possibly hundreds of metres away. As the chicks are unable to fly so soon after hatching, any impassable obstacles encountered on the way can usually be negotiated by the parents simply airlifting their chicks over to the other side. The feeding behaviour of the chicks seems most closely to resemble that of back-garden chickens, with the chicks scratching around the central figure of their mother while they search out beetles, larvae and earthworms. They also feed like their parents, by moving and scanning, with any chick straying too far instantly called back to the fold. Despite being able to find more than enough food themselves, they can initially struggle to keep warm during poor weather so will still disappear under their mother to be brooded on cold, wet days and each night.

For the few days before they eventually break free of their ovoid prison, the incarcerated Peregrine chicks will begin cheeping to their parents, who often respond, before becoming noticeably more restless as they prepare for the
youngsters' arrival. The chicks will usually emerge within the space of a couple of days, although not all eggs will necessarily hatch, as a small proportion tend to be either infertile or suffer from the embryo having died during incubation. After their exertions to break free the young will initially be weak, wet and exhausted, but then quickly dry out into fluffy, white chicks. Unlike the Lapwing youngsters, the Peregrine chicks hatch in a far less advanced (or altricial) state and so are utterly reliant on their parents for some months before they are able to catch their own food. Upon hatching, the parents don't bother to remove the eggshells, which instead are trampled into the nest by the chicks and parents over time.

The appearance of the chicks will result in the parents suddenly turning much more aggressive and intolerant of trespassers, driving any non-related Peregrines and potential predators away from the nest site. With just their first coat of down to protect them from the elements the young can be incredibly prone to chilling, and so will initially be brooded almost continually by the female. Huddling together to conserve heat, the young are then fed tiny morsels of food by their mother as they take the first of many meaty meals caught and brought in by their diligent father. Even when the chicks are small it won't take long for a hierarchy to develop within the brood, with some chicks always demanding to be fed first, while any weaker chicks are forced to feed afterwards. In lean times, small chicks can often quickly disappear from the nest, but in years of plenty the entire brood may well stand a good chance of surviving, certainly as far as fledging.