Harriers in the Central Mediterranean

HARRIERS IN MALTA

Studies carried out through intensive observations over many years have shown that Malta is one of the most important crossing places for harriers in both spring and autumn.

There is a large body of data of observations of birds of prey migration in autumn, the oldest of which can only be taken to be indicative for a number of reasons. First of which is the original observation points. Over the years, Michael Sammut and Natalino Fenech realised that by staying in the ‘traditional’ watch posts at Buskett, a large woodland garden close to the western coast, we were missing many birds that flew from the west, north and east. Two areas on the western coast have now been identified as much better places to observe migrating raptors, while the area around Buskett remains important mainly for those birds that roost, as most of the migratory birds are also seen from one or both of the other two spots.

Migration of harriers

Since our foundation is mostly concerned with harriers at the moment, we shall focus some discussion about harrier migration through the Maltese Islands. Four species of harriers occur, the most common of which is the Marsh Harrier, followed by the Montagu’s harrier, Pallid is more scarce but appears in good numbers, while Hen Harriers are rare and only a few are recorded. All the first three species appear in both ‘spring’ and ‘autumn’.

There is a very interesting pattern with harrier migration. First of all when speaking about ‘spring’ and ‘autumn’ migrations, one has to keep in mind that these are very broad terms and do not specifically refer to the seasons that start on 21 March and 21 September, but refer to the return migration in spring, that can start in the last week of January, and the outward migration from the breeding areas, that for harriers in Malta can mean any time after mid-August, sometimes earlier too. Individual birds are usually seen in the initial days, but it is not unusual to see several birds together in suitable habitat, even out of season.

Marsh Harriers

Marsh Harriers are very common spring and autumn migrants seen between early February and May and from early or mid-August to early November. It is occasionally seen in mid-June and December and January. It is not known if the December and January sightings are late ‘autumn’ migrants, early ‘spring’ migrants or whether these would be birds from those wintering just over 60 km away in Sicily.

Harriers usually spend between a few hours, sometimes a few weeks in the same areas in spring, but in autumn, birds arriving late and roosting in communal roosts, sometimes consisting of over 300 birds, start leaving their roosts 15 minutes before sunrise and sunrise, up to 70 per cent of the birds would have left. When they roost in spring, they choose tall grass, usually cereal, but in autumn they mainly roost either in reed beds.

Montagu’s Harriers

The Montagu’s Harrier is a fairly common migrant in spring and rather scarce in autumn, when individuals may appear as early as late August. Most are seen between March and May. Although it is mostly seen singly, loose parties of six or more birds are not uncommon in spring, especially towards the end of April, when dozens, sometimes over 200 birds may be seen within a very short span of time.

Several of these birds often roost together in the same fields in spring. Singles are usually seen in autumn but up to eight in a day have been recorded. When they roost in spring, they roost in the same areas as Marsh Harriers, in tall grass, but they may also roost in the open, one or two metres away from each other on the ground, especially when large numbers of birds are involved.

Birds from Poland and Germany have been recorded in Malta through ringing, but a satellite tracking project involving a male showed the bird to be breeding south of Moscow and wintering in South of the Sahara.

Pallid Harriers

The Pallid Harrier is a scarce migrant and singles are usually seen mostly between early March and May and from August to mid-November. Highest counts are normally recorded in spring and much fewer birds are usually seen in autumn. Although the Maltese Islands are small, and birds can appear anywhere, there are several areas where Pallid Harriers always appear.

The airport grounds at Luqa are undoubtedly the best place where Pallid Harriers can be seen in good numbers, with more than 10 being recorded in the area, sometimes for several days. There are other areas in the north, such as the Burmarrad, Magħtab, Bidnija agricultural areas, and Tas-Silg in the south, where particular fields, usually the larger ones, are prime habitat for Pallid Harriers. In other words, if birds are around, you can be sure to see one or more in these places, but highest counts will be from the airport.

There are no known ringing recoveries of harriers, so where these came from and went to were quite a mystery. The same satellite tagging project referred to reveal an interesting pattern with birds probably breeding in areas close to Nenets Autonomous Okrug in Northern Russia and then migrated south and the latest opposition in December was in Niger.

Hen Harriers

The Hen Harrier is usually seen in March and April, occasionally in May and July. It is rare from August to October but occurs more frequently between November and January. Single birds or parties of up to three birds have been seen, but a flock of eight has also been seen.

Migration pattern

There is a very interesting pattern with harrier migration through Malta. In spring, Marsh, Pallid and then Montagu’s are usually seen in that order. In autumn, Marsh harriers appear first, then Montagu’s and Pallid Harriers appear later.

Harrier Conservation International

Future studies by our foundation may help to unravel the complex migration pattern in the Central Mediterranean, which is very little known.