AUTUMN MIGRATION IN SOUTHWEST PORTUGAL, 1957

1958 JENNIFER OWEN : MIGRATION IN S.W. PORTUGAL 515

AUTUMN MIGRATION IN SOUTHWEST PORTUGAL, 1957.

By JENNIFER OWEN.

Received on 29 January 1958.

INTRODUCTION.

Several interesting problems have been raised with regard to autumn migration in the Cape St. Vincent area of southwest Portugal. Until 1956, when the area was visited by Moreau and Monk (1957), the only published observations were those of Steinfatt (1933). The problems may be stated as follows:-

1. Is a large autumn passage as found by Moreau and Monk (1957) a regular feature of the area, and how consistently does it take place throughout the migration period ?

2. With what types of weather are large numbers of birds on the south coast associated ?

3. On what compass-bearing do birds leave southwest Portugal ? As may be seen in Fig. 1, birds from most parts of Europe reaching Cape St. Vincent

FIGURE 1. The Iberian and neighbouring coasts.

. 100 MILES

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on their autumn migration would have to turn through an angle of at least 45 degrees to reach Africa. Otherwise their only landfall is the Canaries, which are 500 miles distant and very small. There are very few observations of autumn migrants in the Canaries but Bannerman (1920, 1932) records many of the species that have been observed at Cape St. Vincent.

A party of six, from Oxford, Cambridge and London Universities, visited the Cape St. Vincent area in the late summer of 1957. The chief places visited are shown in Fig. 2. The party, comprising R. W. Arnold, R. A. F. Cox, C. J. Henty, D. F. Owen, C. M. Perrins and the author, arrived at Sagres on 23 August. There R. A. F. C. stayed until 2 September, D. F. O., C . M. P. and the author until 17 September, and R. W. A. and C. J. H.

FIGURE 2. The Cape St. Vincent area of southwest Portugal.

until 9 September when they left for Vila Nova de Milfontes 50 miles north of Sagres on the west coast of Portugal returning to Sagres 13-25 September. Our visit was therefore at a time of year when night migration might be expected to be at its peak. In fact, we saw great numbers of small passerine night-migrants throughout the period, except for brief intermissions which could be attributed to weather conditions to the north. Although visible migration did not occur in quantity we were able to observe a number of departures from the Cape St. Vincent area at dawn and at dusk, in a south or southeasterly direction, on which course the journey to the African coast would be less than 300 miles. We took a mist-net with us, and in all 176 birds were caught, mostly small passerine night-migrants. The day-to-day fluctuations in the numbers of birds caught corresponded with the daily variations in the numbers of small migrants seen in the area but not caught. There were several marked peaks in the volume of small passerine night- migration as estimated by mist-netting. For example, on 22, 23 and 24 September we caught 107, 173 and 106 birds respectively, despite only 5 on 21 September and 12 on 15 September.

The Cape St. Vincent countryside is arid, the predominant vegetation being low aromatic scruh and the streams dry in the summer. Except at the

1958 JENNIFER OWEN : MIGRATION IN S.W. PORTUGAL 517 Montinhal beach there are 150-foot cliffs all round the coast, and a mile or so inland run a series of outcrop ridges, those to the immediate northwest of Sagres being topped by small pine-woods. The few patches of tall vegetation are conspicuous, particularly an interrupted line of Pittosporum bushes up to 8 ft. tall and 8 ft. wide, stretching for half a mile along the Cape St. Vincent road, and the cultivated fig-groves, low vines and maize fields surrounded by windbreaks of Arundinaria canes and Agave americana.

According to local information the area normally receives hardly any rain from March until November. Temperatures are consistently high during the late summer and skies clear, except on mornings when the prevailing northwesterly wind brings in an Atlantic mist, which usually clears by 11.30. Both this wind and the mist (which was occasionally associated with a southwesterly wind as well) are probably due to the fact that the Cape St. Vincent peninsula projects into cold Atlantic currents. Most evenings and during the whole of 13 September, the northwesterly wind freshened. Exceptions to the prevailing northwesterly wind were the following: 27 and 28 August, 6 and 15 September, wind light easterly during the early part of the day: on the night of 16 September light southeasterly; 16-21 September, winds varying between southeast and southwest, but the winds with south and east in them were never above Force 3. On 9, 12 and 13 September at both Sagres and Vila Nova, and on 14 September at Sagres, some cloud persisted all day.

Except for 4 September, when we visited Monchique some distance inland, a continuous watch was kept for migrants in the Sagres area. I n particular we watched at dawn every day either on one of the Sagres headlands, at the Cape St. Vincent lighthouse 4 miles to the west, on a high ridge 2 miles inland, or on the coast between Sagres and the lighthouse. In addition we used mist-nets to catch night migrants sheltering in the Pittosporum bushes, in a fig-grove and in other cover. Finally, dusk watches were kept, mainly on the Sagres headlands and along the Cape St. Vincent road, and one night watch at the lighthouse.

We found that by using mist-nets we were able to gain a feasonably accurate impression of the volume of migration on the previous night. We often erected our mist-net in the middle of a row of fig-trees in the Montinhal valley and drove the birds from the surrounding area into the net. The trapping technique differed for the Pittosporum hedge as the birds were so loth to leave its shelter, and it was possible for two of us to hold the net between each bush and the next while the rest acted as beaters. There were enough of us to prevent many birds breaking awav, and as it was a single line of bushes most birds that flew forward were caught at subsequent bushes. Thus, every day a large proportion of the birds sheltering in the hedge were caught. As only two of our party remained during 17-25 September, the drive along the hedge was not completed on every day in this period.

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There were sometimes so many night-migrants sheltering in the area, that birds were caught simply by placing a net behind even the smallest of bushes. One Whitethroat Sylvia communis was caught by hand. A Spotted Crake Pmzana porzana was caught by dropping the net over the bush in which it had taken shelter. In addition, a few waders were caught on the Montinhal beach by using a clap-net. In all we caught 176 birds* and ringed them with Portuguese rings supplied by Professor Santos- Junior of Oporto University.

The main scene of operation of the local bird-catchers was the same row of Pittospurum bushes that interested us. They baited small spring-traps with large ants or a type of beetle larva, and placed them in the bushes. Like us they caught chiefly Whitethroats and Nightingales Luscinia megarhynchos, with occasional Melodious Warblers Hippolais polyglotta and other species. Soon after we commenced operations their trapping was stopped by the local authorities.

Acknowledgments. We are indebted to Eng. Saldahna Lopes of Lisbon for information and

help during our stay in Portugal, to Eng. Rosado Nunes of Far0 for an introduction to the country around Sagres, to Capt. Laurencio Duarte for his frequent visits to Sagres with rings and enthusiasm, to Professor Santos- Junior of Oporto University for the Portuguese rings, to Mr. G. M. Tait, O.B.E., of Oporto for help in planning the original trip scheduled for 1955, and to all the people of Sagres village who showed us kindness, constructive criticism and practical help with mist-netting.

SMALL PASSERINE NIGHT MIGRANTS.

General. There was an irregular, but often large, passage of small passerine night-

migrants in the Cape St. Vincent area during the whole of our stay. By day the birds sheltered in any sort of cover, however sparse, as recorded by Moreau & Monk (1957). On one occasion, 15 warblers were sheltering in a bush of Palmetta sp. about 18 inches high on the exposed cliff-top. Over the whole period the commonest small passerine night-migrants, both seen in the field and caught in the mist-net, were Nightingales, Whitethroats

.Spotted Crake Porsana porzana 1 , Turnstone Arenaria interpres 4, Hoopoe Upupa epops 3, Wryneck Jynx tmquilla 44, Golden Oriole Oriolus oriolus 1, Black-eared Wheatear Oenanthe hispanica 1 , Redstart Phoenicunu phoenicurus 19, Nightingale Luscinia megarhynchos 285, Grasshopper Warbler Locustella naevia 9, Reed Warbler Acrocephalus stirpaceus 30, Sedge Warbler Acrocephalus schoenobaenus 51, Melodious Warbler Hippolais polyglotta 57, Orphean Warbler SyloM hortensis 8, Garden Warbler Sylvia borin 387, Whitethroat Sylvia communis 786, Garden WarblerIWhitethroat Sylvia borinlcommunis 1, Sardinian Warbler Sylvia melanocephala 10, Subalpine Warb- ler Sylvia cantillans 10, Rufous Warbler Agrobates golactotes 1, Willow Warbler Phylloscopus trochilus 48, Chiffchaff Phylloscopus collybita 2, Pied Flycatcher Muscicapa hypoleuca 8, Tawny Pipit Anthus campestris 1, Yellow Wagtail Motacilla flava 1 , Woodchat Shrike Lanius senator 8.


and Garden Warblers Sylvia borin. Other common migrants both seen and caught were Redstarts Phoenicurus phoenicurw, Reed Warblers Acrocephalus scirpaceus, Sedge Warblers Acrocephalus schoenobaenus, Melodious Warblers, Willow Warblers Phylloscopus trochilus, Pied Flycatchers Muscicapa hypoleuca, and Woodchat Shrikes Lanius senator. were seen frequently, and Spotted Flycatchers Muscicapa striata, with Redstarts, Phylloscopi and Pied Flycatchers were particularly common in the pine-woods throughout most of the period. Some of these species were very conspicuous (e.g. Pied Flycatcher), while others were not (e.g. Reed Warbler), but the latter were shown to be present by mist- netting.

Several other species were considered as migrants although there was no evidence for a marked passage. Stonechats Saxicola torquata were resident in the area but a slight increase in numbers 15-18 September indicated some movement. Grasshopper Warblers Locustella naevia were difficult to observe but nine were caught in the mist-net on different days, chiefly in the Pittospo- rum bushes. Several Olivaceous Warblers Hippolais pallida were seen in a clump of olive trees at the head of the Montinhal valley on 12 September. Orphean Warblers Sylvia hortensis were frequently seen near Sagres, although in small numbers, and eight were caught. Sardinian Warblers Sylvia melanocephala are resident in the area but slight fluctuations in numbers suggested some movement. Subalpine Warblers Sylvia cantillans were also present throughout the period with slight fluctuations in numbers, indicating passage, particularly on 9 September when five were caught. Juvenile birds of this species were difficult to identify until they were caught, and could be confused with Spectacled Warblers Sylvia conspicillata, a few of which were' seen in Montinhal valley when we arrived, but none after 26 August. Single Rufous Warblers Agrobatesgalactotes were seen on 29 and 30 August and 3 September. The Chiffchaff Phylloscopus collybita is resident in the Iberian peninsula but was not common at Sagres during our stay; of the Phylloscopi caught, only two were Chiffchaffs.

Most of these small passerine night-migrants, including some of the less common ones, were also seen at Vila Nova 9-13 September. At Sagres, numbers of the more common species fluctuated considerably from day to day, and by using mist-nets it was often possible to show this quantitatively (see Appendix).

Nightingales, Whitethroats and Garden Warblers behaved in such a way as to make the numbers of each caught at different times on any one day directly comparable. The similarity of the trapping technique during the whole period allows a comparison between the numbers of any one species on different days. Reed Warblers, Sedge Warblers and Grasshopper Warblers skulked in the lower branches of the bushes, Redstarts were wary and broke away, and

Whinchats Saxicola rubetra .

Different species reacted to the net in different ways.

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Phylloscopi and Subalpine Warblers were able to fly through the mesh of the net, thus these smaller birds were not so often caught.

Fluctuations in numbers. Birds caught on successive days in the mist-net may, however, be used as

an indication of the number of small passerine night migrants present in the area. On 3 September in the Montinhal valley and along the Pittosporum hedge, 140 birds were caught, on 2 September 69, and on 5 September only 25 (4 September was spent at Monchique). On 15 September 129 were caught, compared with 39 the day before and very few on subsequent days until 22,23 and 24 September when 107,173 and 106 birds respectively were caught in the Pittosporum bushes alone, the numbers dropping again on 25 September to 12 (see Appendix). Such large totals of night-migrants tended to correspond with days when other night-migrants that were not caught were common.

These fluctuations in the numbers of birds caught represent mainly fluctuations of the three commonest species, Nightingale, Garden Warbler and Whitethroat. The peaks of movement for these species did not coincide although all were present in some numbers throughout most of the period. Nightingales were particularly common until the end of August, White- throats increased in numbers until 11 September, when 60 were caught, and Garden Warblers which were first seen on 29 August, reached a peak on 23 September when 103 were caught. There were small but marked peaks of other species that do not become evident in a consideration of total numbers of birds caught each day. Thus, we first saw Reed Warblers on 3 September and after this they were frequent but never common, with small, but marked, peaks on 15 September and on 24 September when nine were caught. Sedge Warblers first appeared on 26 August, and they were present and locally quite common until 31 August when there was a decrease; on 15, 16 and 17 September there was a small influx into the Sagres area. Of the species that were not caught, Whinchats were not seen until 2 September, after which they became increasingly common until 12 and 15 September when hundreds were seen. Spotted Flycatchers and Redstarts were especially common in the pine woods on 7 September, and Redstarts on 15 and 22 September.

Few small passerine night-migrants were seen or caught on 8 September or 16-21 September. The initially heavy passage of Nightingales declined on 16 September. There was a marked decrease in Whitethroats, Phyl loscop~~ spp. and Sedge Warblers on 28 August, and on 17 September we saw no Garden Warblers or Phylloscopi, the latter thereafter never increasing to their former numbers. The absence of Melodious Warblers from any of the areas visited was conspicuous on 10, 14 and 15 September, when other small night-migrants were common.

In contrast there were days when some species were not recorded.


The total population of the Pittosporum bushes was estimated on three days using the trap and retrap method (see Ford 1945). The formula used is p = 2 , where p is the estimated population, x the total number of birds caught on the first drive of the hedge, y the total caught on a second drive, and I the number of retraps in the second drive.

I

Thus, we have:-

Estimated Date 1st. catch (x) 2nd catch ( y ) Retraps (z) Population ( p )

30 August 50 42 11 191 11 September 72 46 20 166 15 September 119 36 14 306

All species taken on any one drive are included in the totals. The only assumption necessary in this calculation is that there is no movement into the hedge during the time between the two catches. Any movement out of the hedge should affect ringed and unringed birds in the same proportions as their relative numbers in the bushes after the first catch, and therefore does not invalidate the method. The Pittosporum bushes were the only broad- leaved cover and the only suitable cover in the area. It appeared from observations before dawn, that birds that had just arrived in the locality flew straight into the shelter of the hedge, and they tended to remain there until they continued their migration at dusk. These estimated values for the total population of the hedge on these three days accord with field observations. Therefore it seems reasonable to use this method for estimating the total population of the hedge on any day, and it should prove valuable to a quantitative study of migration in an area such as this.

Numbers in relation to weather. The following observations refer only to those species which were caught,

and we have little information about the fluctuations of birds, such as the flycatchers, which frequented the pine-woods.

The local weather, described in the Introduction, cannot be expected to influence migration into the area to any great extent but it must have some effect on birds leaving. Thus, local weather may be the reason why a Sedge Warbler ringed on 17 September was retrapped on 18 September, a Whitethroat ringed on 18 September retrapped on 21 September and a Garden Warbler ringed on 23 September retrapped on 24 September. We have compared our observations of birds in the Cape St. Vincent area with the Daily Weather Maps, but any attempt at correlating the weather and the amount of migration in an area such as Cape St. Vincent is subject to the following factors :-

1. It is impossible to state even approximately how far or from what precise direction any bird has flown during the preceding night.


2. Presumably any bird reaching Cape St. Vincent (or any similar area) and faced with a sea-crossing would be more likely to continue if the local weather was good than if it was unsuitable. Thus it is not certain whether the absence of birds at Sagres indicates a lack of night migration.

A cold front to the north of Sagres on 25 August had moved southeast over the area and reached Gibraltar by the morning of 26 August. Birds were few on this day, but Sedge Warblers were surprisingly common. Another cold front which formed in the northwest of the Iberian peninsula on 2 September, moved south over Portugal and parts of Spain on 3 Septem- ber, but by 4 September had retreated to the Pyrenees. Unfortunately no observations were made on 4 September, but the day before, 140 birds were caught including 88 Whitethroats. On 5 September, however, only 25 birds were caught, and on the next day only 46, perhaps indicating that the cold front had blocked movement into the Iberian peninsula over the Pyrenees on 4 September. On 8 September after an overcast night during which a cold front had reached the Lisbon area from the north, only nine birds were caught, and on the next day, when the front had moved over the Sagres area during a lightly overcast night, 73 birds were caught in all. On 10 September, when the cold front had reached Gibraltar, causing cloudy conditions to the northeast of Sagres, only 17 birds were caught. Next day when the skies to the north and east had cleared, 82 birds were caught.

Yet another cold front reached north Iberia on the night of 11 September and it was on the following day, after a clear night in south Portugal with a northwesterly wind, that Whinchats were common though the other species had not increased in proportion. On 13 September as the cold front moved south 46 birds were caught, and on 14 September when the front had moved over Sagres, only 39. It was the following day after a mainly overcast night with east winds in northeast Spain that we caught 129 birds including 66 Garden Warblers. During the period 16-21 September few night-migrants were seen at Sagres; the nights of 15, 16 and 17 September were overcast and on the night of 18 September a cold front moved over the area. During all this period winds were light and variable with an easterly tendency, and doubtless the cold front affected the numbers caught on 20 and 21 September, when they amounted to only two and five respectively. On 22 September, after a night of good settled conditions throughout the Iberian peninsula, and a light northwest wind, 107 birds including 54 Whitethroats were caught in the Pittospururn bushes alone. This weather continued for two days and there were many birds in the area, but on 25 September, when the weather was the same (despite a heavy local morning mist) we caught only 12 birds.

At no time during our stay did we experience a prolonged spell of east winds and we could not therefore test earlier reports (Moreau & Monk 1957) that with east winds there is little migration in southwest Portugal. During


a period of light variable winds frequently easterly, from 16 until 21 Septem- ber, birds were scarce. Moreau & Monk state that although east winds are associated with a paucity of small migrants on the south coast, this does not apply to the west coast; at Vila Nova they had quite large numbers of birds with light easterly winds, whereas with northwest winds we had very few there. The large numbers of Sedge Warblers that we caught over the whole period are of particular interest as this bird does not breed in the Iberian peninsula, The days when this species was most common, 29 and 30 August, followed fine clear nights with a light northwesterly wind.

General behaviour. Most of the small passerine night-migrants were feeding during the day

on the berries of the Pittosporum, the fruits of Daphne gnidium or ripe figs. We saw a Nightingale brush against a small bush of Cistus sp., where its wings caught fast on the sticky leaves. Though there were some resident raptors we rarely saw one take a small bird. Once a Kestrel Falco tinnun- culus was seen to chase a Garden Warbler on the cliff tops. Twice, a large snake, probably Celopeltis monspessulana, was seen to take a small bird, once a Whitethroat and once a Nightingale.

Behaviour at dusk. On 27 August, two Phylloscopi were seen flying high in a south-south-

easterly direction at 18.00, three hours before sunset. On 15 September it was clear and still at dusk, and a watch was kept by the Pittosporum bushes which during the day had been full of migrants. Sunset was at 19.30 and between 20.15 and 20.20 the warblers all left the bushes. They flew strongly, singly or in groups, and left without hesitation, taking a south-southeasterly course. The speed and determination of the whole manoeuvre was striking, as was the synchronisation. Again, on 18 September when the sky was clear and the wind northwest, four warblers were seen flying southeast at dusk.

On the nights 9, 10, 12, 15, 16, 18 and 20-24 September, when at dusk it was clear with a light to moderate northwesterly wind, Tree Pipits Anthus trivialis and Short-toed Larks Calandrella brachydactyla were heard flying high, south or southeast, between 20.00 and 20.30. These are the only two species for which we have evidence of both day- and night-migration.

Observations at Cape St. Vincent lighthouse. The lighthouse-keeper told us that on misty nights later in the year

numbers of birds strike the light. On the night of 19-20 September between 11.15 and 01.40 two of us watched by the lighthouse. The wind was light southwesterly and the sky was overcast. At midnight it was rather misty. Only one Nightingale and six other small passerines were seen at the light, although many waders and terns came from the north.


VISIBLE MIGRATION OF SMALL PASSERINES.

During the period 24 August to 25 September, visible migration of small passerines at Sagres, Cape St. Vincent and Vila Nova was spasmodic and never on a large scale. We watched at dawn and during the first hour of daylight every day, and on several occasions at dusk. Only on 10, 15, 22, 23, 24 and 25 September did we see more than 50 migrants and frequently when the weather seemed good we saw only 10-15 of such birds in the day. We saw no large groups of migrating birds, only single ones or flocks of 5-10. ,On some days we watched at more than one place at dawn, usually at Cape St. Vincent, Sagres Point and Baleeira Point; and sometimes at the Montinhal beach, at Vila Nova, at Lagos and on a hill two miles inland from Sagres.

The commonest small passerine day-migrants were Tree Pipits and Yellow Wagtails Motacilla Java, but in addition we saw Short-toed Larks, Tawny Pipits Anthus campestris, White Wagtails Motacilla alba, Grey Wagtails Motacilla cinerea, Corn Buntings Emberiza calandra and Ortolan Buntings Emberiza hortulana, passing over the Cape St. Vincent area at .dawn or dusk. There were few Tree Pipits when we first arrived but they became increasingly common towards the end of our stay. Motacilla Java .iberiae was common at Sagres and Vila Nova, and M . f . Javissima was seen near Sagres on 27 August and 15 September; M. f . Jaoa was not definitely identified although reported by Moreau & Monk (1957). Short-toed Larks were present at Sagres and Vila Nova throughout the period, and were seen apparently migrating on several occasions. C. rufescens was not certainly identified although probably present. Tawny Pipits were common during the day at Sagres and Vila Nova throughout our stay. White Wagtails were occasionally seen on the Montinhal beach and single Grey Wagtails were seen at Sagres on 24 August, 6 , 7 and 15 September, and at Monchique on 4 September. Five Corn Buntings were seen near Cape St. Vincent on 9 September and one at Lagos on 17 September. We saw Ortolan Buntings in small numbers on 6 September, and regularly during the period 15-26 September.

We tried, as with the small passerine night-migrants, to establish a correla- tion of local and general weather with the daily fluctuations in the numbers of wagtails, pipits and buntings.

After 6 September there was some visible migration at Sagres on any day when the wind was northwesterly light to moderate. There was a sudden increase in the volume of migration of Yellow Wagtails at both Sagres and Vila Nova on the morning of 10 September, after a rainy day on 9 September. The period 16-21 September, when the winds varied from south to east, was as poor for visible migration as it was for night migration, and no Ortolan Buntings were recorded. On 22, 23 and 24 September when the wind was northwest, and there were large numbers of night-migrants, three, ten .and two Ortolan Buntings were recorded.

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Tree Pipits and Short-toed Larks were heard and sometimes seen flying over Sagres at dusk. We recorded Tree Pipits (up to 10 seen) regularly during the period 9-24 September, and Short-toed Larks on 10, 15 and 16 September (up to six seen). On most of these occasions the wind was north or west, light to moderate, and the sky was clear.

Although the total volume of migration was small and there was hardly any before 6 September, the fluctuations in numbers at all the places we watched seemed to bear some relation to each other. Any observed differences at different places at dawn were attributed to local wind direction. Thus, on 16 September when the early-morning wind was light easterly, it seemed that Tree Pipits and Yellow Wagtails from the north were flying south along the west coast to Cape St. Vincent and out to sea. Consequently very few were seen at Sagres that morning. But on 24 September when the wind was light to moderate north-northwesterly many more wagtails and pipits were seen at Sagres than at Cape St. Vincent, indicating that under these conditions migrants cut across the peninsula.

The direction by which migrants leave the Cape St. Vincent area is of particular interest in view of its geographical position. Most of the Short- toed Larks, Tree Pipits, Tawny Pipits, Yellow Wagtails, and Ortolan Buntings observed left the Sagres area in a south or southeasterly direction over the sea. Yellow Wagtails and Tree Pipits sometimes turned east at Cape St. Vincent to fly along the coast, but only a few were seen coasting at any point east of Sagres Point. Many birds converged on Sagres Point from the northwest, north and northeast, but all left this point on a south or southeasterly compass-bearing, and those that we watched until they were out of sight over the sea, all flew south or southeast, except a party of four Tree Pipits which flew southwest. Many birds that we saw did not turn southeast until well out over the sea. All the Tree Pipits and Short-toed Larks observed at dusk left the Cape St. Vincent area in a south or southeasterly direction.

Although we saw little migration of pipits and wagtails at Sagres, there was a marked preference to depart out to sea in a south or southeast direction.

OTHER MIGRANTS.

Herons and storks. A single Black Stork Cicmia nigra was seen on 25 September at Sagres

soaring with two Egyptian Vultures Neophron percnopterus and two Black Kites Milvus migrans. One or two Herons Ardea cinerea were seen at Sagres, usually in the early morning, flying high out to sea and east or southeast (once south-southwest) ; they were common at Vila Nova where there were feeding grounds. On 19 September at 10.40, a party of seven was seen flying along the coast towards Lagos. A party of Purple Herons Ardea purpurea was heard at 06.15, before daybreak, on 2 September flying

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over Sagres, but their direction was not established. Little Egrets Egretta gurzettu were common on the estuary at Lagos, and small parties were occasionally seen in the Cape St. Vincent area. Three Cattle Egrets Ardeola ibis were feeding in the fields at Vila Nova on 10 September, and one on 12 September. White Storks Ciconiu ciconiu were not expected near Sagres because they are well known to depend on thermals and favour short sea- crossings, but one was seen at Lagos on 4 September and many in the fields north of Lisbon on 18 September. On the evening of 15 September we saw a small unidentified heron flying southeast at dusk near Sagres.

Birds of prey. We saw few birds of prey in the Cape St. Vincent area during the period

23 August to 25 September, and very little evidence for their migration. All big migratory raptors except harriers Circus spp. appear to leave the Iberian peninsula mainly by the short Gibraltar crossing. There is a similar con- centration at the Bosphorus in the eastern Mediterranean. Most of the observations are for spring migration, but the same seems to hold good for the autumn, and although harriers have been seen in the open Mediterranean, the other raptors seem loth to undertake a long sea-crossing (Moreau 1953).

At Cape St. Vincent it was not always easy to determine which of the raptors we saw were on migration, as all the observed species are reported to breed in the area and all except the Black Kite and Montagu’s Harrier Circus pygurgw may winter there too (Peterson, Mountfort & Hollom 1956). Both Marsh Harriers C. ueruginosus (considered to be partial migrants), and Montagu’s Harriers (summer visitors to the area) regularly hunted up and down the cliff-top near Cape St. Vincent and on the inland scrub, throughout the period. Several times a single Montagu’s Harrier was seen flying out to sea in a south-southeasterly direction. On one occasion, a juvenile of this species was stalked to within 6 ft. after it had settled on ;k mound of stones at dusk. Single Hen Harriers C. cyuneus were seen OIL 1 and 7 September at Sagres.

We saw Black Kites at both Sagres and Vila Nova, and Red Kites Milwus milwus at Sagres on 28 August, 1 and 11 September. They both breed in the area and the Red Kite winters there. The slight daily fluctuations i n numbers of these conspicuous birds indicated some movement; on 1 Septem- ber two parties of four Black Kites were seen flying south-southwest, on 2 September one party of eight flying high and southeast and couples on 9, and 11 September. These observations were made some distance inland and Black Kites were never seen flying out to sea. As many as four Black Kites were seen together feeding on a rubbish tip.

Two Bonelli’s Eagles Hieruetus fusciutus were seen on 28 August over the pine-woods and singles on 29 August (pine woods), 3 September (Montinhal valley) and 7 September (Cape St. Vincent). One or two Egyptian Vultures,

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mostly juveniles, were seen on several occasions; this species too is resident in the area and they may not have been migrants, although the different plumages indicated that they were not always the same birds.

One Hobby Falco subbuteo was seen on 10 September and one Sparrow- hawk Accipiter nisus on 28 August, both at Sagres.

The small amount of raptor migration is of special interest in view of the large numbers that pass at Gibraltar. On 2 September, the day most ideally suited to raptor migration, a total of only eight birds was seen. On subsequent dates there was no visible movement at all. Like bee-eaters, raptors, being high-flying, may see the prominence of the Cape St. Vincent peninsula from some distance and cut across inland without touching it. However, watches some miles inland and at Vila Nova did not indicate any different numbers there. Moreau & Monk (personal communication) saw almost no birds of Prey *

Quail. A Quail Coturnix coturnix was flushed from the head of the Montinhal

valley on most days, an occasional one on the Sagres headlands and several at Vila Nova, but on 15 September, following a fine windless night, eight were seen around Sagres. In view of the fact that we covered the same ground on most days, and that Quail would only become obvious if we all but trod on them, this sudden increase must represent a considerable influx of birds into the area. At dusk on 15 September a probable Quail was seen flying southeast. The Quail breeds throughout the Iberian peninsula and winters in Portugal and south Spain.

Waders. The following waders were regularly seen in the Sagres area; Oystercatcher

Haematopus ostralegw, Ringed Plover Charadrius hiaticula, Kentish Plover Charadrius alexandrinus, Turnstone Arenaria interpres, Curlew Numenius arquata, Whimbrel Numenius phaeopus, Bar-tailed Godwit Limosa lapponica, Green Sandpiper Tringa ochropus, Wood Sandpiper Tringa glareola, Common Sandpiper Tringa hypoleucos, Redshank Tringa totanus, Greenshank Tringa nebularia, Knot Calidris canutw, Little Stint Calidris minutus, Dunlin Calidris alpina, Sanderling Crocethia alba.

Little Ringed Plovers Charadrius dubius were regularly seen at Lagos but not at Sagres. We saw single Golden Plovers Charadrius apricarius at Sagres on 2 and 6 September, and one (tame) Dotterel Charadrius morinellus on Baleeira Point on 8 September. Single Snipe Capella gallinago were seen at Sagres and Cape St. Vincent on 26 and 30 August and 16 September, and a Curlew Sandpiper Calidris testacea on 22 September. There was one Ruff Philomachus pugnax on the Montinhal beach on 14 September and a single Black-winged Stilt Himantopus himantopus at Lagos on 19 Sep- tember. We saw a single Stone Curlew Burhinus oedicnemus above the.

2L2


Montinhal valley on 30 August, and about six at Vila Nova on 11 September. On the night of 19-20 September, when a watch was kept at the lighthouse

between 11.15 and 01.40, many waders came from the north and turned east on reaching the point. Redshank, Ringed Plover, Turnstone, Dunlin, Common Sandpiper, Greenshank, Sanderling and Knot or Bar-tailed Godwit were heard and many of them seen, and no doubt other species were involved.

Sea-birds. We saw no large movement of sea-birds in the Cape St. Vincent area,

in contrast to the impressive movements in northwest Spain (Snow, Owen & Moreau 1955). It was difficult to say which, if any, of the sea-birds were in fact migrating. Balearic Shearwaters Procellaria puflnus mauretanicus, Cory’s Shearwaters P. diomedea and Herring Gulls Larus argentatus were always present in great numbers feeding. Sandwich Terns Sterna sand- wicensis and CommonlArctic Terns Sterna hirundo/macrura were heard and seen at the lighthouse on Cape St. Vincent on the night of 19-20 September.

Two Sooty Shearwaters Procellariagrkea were seen off Sagres on 3 1 August, Gannets Sula bassana were seen regularly in small numbers but did not show any evidence of migration. Small parties of Common Scoter Melanitta nigra were seen on several occasions off Sagres and Cape St. Vincent: six on 26 August flying east, five on 27 August flying west, 18 on 28 August, 20 on 30 August and six on 16 September. Single Arctic Skuas Stercorariusparasi- ticus were frequently seen (and 10 on 5 September) off Baleeira Point and the Montinhal beach mobbing terns. Lesser Black-backed Gulls Larus fusw were common and were occasionally seen flying east; several Black- headed Gulls Lmus ridibundus were seen off Baleeira Point and the Montinhal beach. Black Terns Chlidonias niger, Common/Arctic Terns and Sandwich Terns were common at Sagres and Lagos and were frequently to be seen feeding together in large flocks on the Montinhal beach. A single Gull- billed Tern .GeZochelidon nilotica was seen at Lagos on 2 September.

Turtle Doves. Tait (1924) reports that after easterly winds in the autumn, there is a

regular and impressive passage of Turtle Doves Streptopelia turtur south down the coast at Oporto and Lisbon, and local information suggests that this also occurs further south. At no time at either Sagres or Vila Nova was there a conspicuous diurnal movement of these birds, and one day of steady east winds, 5 September, brought no Turtle Doves at all. On 1, 2 and 3 September there were small parties about everywhere, but they were flying indeterminately around with no hint of direction. However, considerable numbers were present during the whole of our stay, mainly concentrated in the tall cover of the pine-woods. Frequently in the early mornings, many Turtle Doves were seen on the bare cliff-tops where there had been none the


previous evening; this suggests that there had been nocturnal movement and during the day they dispersed. Once a probable Turtle Dove was seen flying southeast at dusk. The regular presence of large numbers of Turtle Doves in the Sagres area during September is indicated by the fact that sportsmen come there every year for the shooting.

Hisundines and Swift. Like Moreau and Monk, we were struck by the absence of hirundine and

swift passage. There were resident Swallows Hirundo rustica and House Martins Delichon urbica at Sagres, which were gathering on telegraph wires in the evening towards the end of September. On 17 September, 250 House Martins were collected on telegraph wires at Espeche 15 miles inland from Sagres. Single Swallows, Sand Martins Riparia riparia and Swifts Apw apus were seen flying down both the Sagres headlands apparently out to sea, but these species were seen everywhere in ones or twos. A flock of 30 Alpine Swifts Apus mlba was seen regularly near Cape St. Vincent, usually in the early morning and late evening when they could be heard calling. The same number of birds was seen on every occasion, and on one evening at 20.30 they went to roost on the cliffs. The Pallid Swift APUJ pallidus was not identified for certain, and neither was the Red-rumped Swallow Hirundo daurica.

Bee-eaters. On our journey through Spain on 21 August and through Portugal on

23 August we saw many Bee-eaters Merops apiaster (feeding over the fig and olive groves), but on our return journey on 17 and 18 September not one was seen. There were no resident bee-eaters at Sagres, but we saw 150 at 09.30 and 50-60 at 10.10 on 28 August; 50 on 29 August; a few at 14.50, 50 at 16.45 and 8 at 17.00 on 1 September; 65 at 09.15 on 2 September; a small party at 11.45 on 3 September, and single birds on 6,7 and 9 Septem- ber, all in the immediate vicinity of Sagres. One flock was feeding on dragonflies of Sympetrum spp. which were also on migration. On reaching the coast the birds seemed very excited and were calling continuously as they circled upwards overhead, probably using thermals to gain height as do birds of prey. Their calls were last heard from a southerly direction but the bright light made it impossible to observe their departure.

Roller. According to Peterson, Mountfort & Hollom (1956), the Roller COY&

garrulus does not breed in Portugal, but we saw one on 26 August, eight on 27 August, eight on 28 August, two on 29 August, one on 5 September and one on 6 September, mostly in the pine woods. In the early mornings of 29 August, 5 and 6 September, there was east in the wind, and on the evening of 5 Sep- tember it was due east.


Hoopoe. The Hoopoe Upupa epops is a summer visitor to all parts of the Iberian

peninsula and winters in the south of Spain but not, as far as is known, in Portugal. The numbers of Hoopoes fluctuated markedly at Sagres, presumably due to passage migration, although the birds were never seen to be definitely moving by day. Until 25 August there were a few Hoopoes everywhere, particularly on the bare cliff-top and heath-land, but on this day there was a spectacular increase, and on 26 August, 40 were seen together on Baleeira Point. There was a decrease the following day, and they were then scarce for the next few days, although on 8 and 9 September several were flushed from the Pittosporum bushes. On 10 September there were none, and on subsequent days few at either Sagres or Vila Nova, until an influx at Sagres on 15 September. From then until 25 September when we left, there were only a few Hoopoes about. Hoopoes were occasionally seen perched in bushes and three were caught in the mist-net.

Wryneck. Wrynecks Jynx torquilla were seen every day at Sagres, and nine on 9 Sep-

tember at Vila Nova; 44 were mist-netted. Like the warblers, Wrynecks were mainly found in the bushes, but on 13,14 and 15 September when they were exceptionally abundant, they were common on the bare headlands and cliff- tops. On 15 September the Pittosporum hedge was estimated to hold 20 Wrynecks but only seven were caught. The prevailing wind throughout this period of abundance was northwest Force 3. Apparently Wrynecks are regular visitors to the area, as the local people who helped us with the mist- netting knew the species and called it by its Portuguese name " trorisco ", whereas other birds that we judged to be more common were not recognised. We did not see the local bird-catchers trap any. There appears to be conflicting evidence as to the breeding distribution of this species in the Iberian peninsula (Tait 1924, Peterson, Mountfort & Hollom 1956), and therefore the origin of these birds is obscure. Moreau & Monk (1957), who did not reach Sagres until 22 September, saw only two. It is of interest that 43 of the birds we caught had freshly moulted adult plumage, and only one was still in juvenile plumage.

Golden Oriole. Golden Orioles Oriolus oriolus were present in small numbers throughout

our stay, and one was caught in the Pittosporum bushes on 29 August. When- ever we visited the pine-woods and the adjacent overgrown and wooded head of the Montinhal valley, one or two were seen, all but one being juveniles or females; their absence from the open country and cliff-top is not surprising as the nearby pine-woods offered a more suitable habitat. The species is a summer visitor to the whole of the Iberian peninsula.


Other land birds.

and three on 30 ‘4ugust.

26 -4ugust and one on 30 August, all in the pine-woods.

at Sagres on 13 September.

Cuckoo Cucullcs canorus; single birds at Sagres on 26 and 28 August

Great Spotted Cuckoo Clamator glandarius; one on 25 August, three on

Spotted Crake Porzana porzana; a single bird was caught and ringed

\Voodlark I,ullulu arborea; a single bird on 24 August. Wheatear Oenanthe oenanthe; first seen on 10 September at Sagres, and

after this was frequent in small numbers. Black-eared Wheatear Oenaizfhe hispanica ; common when we arrived

but not seen after 12 September when its place was taken by 0. oenanthe. Bluethroat Cyanosylvia soecica; single birds were seen at Sagres on 1 5

September, at Lagos on 17 and 26 September, and at Vila Nova. Robin Eriihacus rubecula; a single bird at Sagres on 5 September. The following species were expected but not seen: Savi’s Warbler Locus-

tella luscinioides, Great Reed II’arbler Acrocephahs arundinaceus, Blackcap Sylzia atricapilla, Bonelli’s Warbler Phylloscopus bonelli.

CONCLUSIONS.

(1) ‘The general impression we gained from our stay at Sagres during the period 24 August to 25 September was of a marked movement of small passerine night-migrants into and out of the area, and some evidence of diurnal migration. On no occasion was there conspicuous visible migration of soaring birds, Turtle Doves, hirundines, swifts, larks, pipits, wagtails or buntings, but large numbers of Bee-eaters were seen on some days.

(2) The prevailing wind during the period was from the northwest, and this wind with clear skies seemed to represent the best conditions for day and night migration in the Cape St. Vincent area. During those periods when the wind moved to the southeasterly quarter, notably 16-21 September, the numbers of day and night migrants decreased. A cold front to the north of Sagres, particularly towards the Pyrenees, seemed to block the movement of small passerine night-migrants into the area; this effect only became appa- rent at Sagres after two or three days.

(3) Many of the migrants observed breed in all parts of the Iberian peninsula (e.g. Whitethroat), others have more northerly and easterly breeding distributions (e.g. Wryneck and Sedge Warbler), and others winter in Portugal (e.g. Quail).

(4) In every case of movement that we watched (of pipits, wagtails and buntings), except one, birds departed from the Cape St. Vincent area out to sea in a south or southeasterly direction. Pipits and buntings were heard migrating at dusk and we judged from their calls that they were travelling south or southeast. Warblers were seen leaving the Sagres area at dusk


and these too took a south or southeasterly course. We have no observations to substantiate Steinfatt's evidence (referring to several weeks later in the season) that migrants leave Cape St. Vincent to the southwest.

SUMMARY.

The Cape St. Vincent area of Portugal was visited in the period 23 August-25 September 1957 in order to watch migration.

There was a marked movement of small passerine night-migrants into and out of the area during the period, Whitethroats, Garden Warblers and Nightingales being the commonest species.

A mist-net was used to catch birds sheltering in vegetation. The daily variation in the number of birds caught was considered indicative of the volume of migration the previous night, and the total bird population in a hedge of Pittorporurn bushes was estimated on three days by the trap and retrap method.

Visible migration of hawks, larks, pipits, wagtails and Bee-eaters was seen but not on a large scale.

Most birds left the Cape St. Vincent area in a south or southeast direction. East winds, cloud and the conditions associated with a cold front inhibited migra-

tion, but there are always acuities in correlating the weather and migration in an area such as this.

Further study of the area east and north of Cape St. Vincent would be interesting.

REFERENCES.

B m " , D. A. 1920. List of the birds of the Canary Islands with detailed refer- ence to the migratory species and the accidental visitors. Pt. 7. Ibia (11) 2 : 519-569.

BANNER&, D. A. 1932. Bull. Brit. Om. C1. 52 : 52. FORD, E. B. 1945. Butterflies. London. MOREAU, R. E. 1953. Migration in the Mediterranean area. MOREAU, R. E. & MONK, J. F. 1957. Autumn migration in southwest Portugal.

Ibis 95 : 329-364.

Ibis 99 : 500-508. PHFKRSON, R., MOUNTFORT, G. & HOLLOM, P. A. D. 1956. A Field-guide to the Birds

SNOW, D. W., OWEN, D. F. & MOREAU, R. E. 1955. Land and sea-bird migration

STBINFAIT, 0. 1933. Vogelzugbeobachtungen auf der Pyrenlien-Halbinsel, Herbst

TAIT, W. C. 1924. The Birds of Portugal. London. WITHERBY, H. F., JOURDAIN, F. C. R., TICBHURST, H. F. & TUCKER, B. W. 1946.

of Britain and Europe. London.

in northwest Spain, autumn 1954.

1932. Vogelzug 4 : 58-65.

The Handbook of British Birds. London.

Ibis 97 : 557-571.

OBSWVATIONS ON THE AUTUMN MIGRATION OF 1957 IN SOUTHERN SPAIN.

With B. Jeffrey I was studying birds in the neighbourhood of Cape Palos, the southeastern corner of Spain, 17 August-2 September 1957 and in the area Algeciras-Tarifa-Vejer 5-12 September. Full records have been sent to Dr. F. Bernis who is publishing a selection in ' Ardeola '. Mean- while the editor of 'The Ibis' has asked me to provide a summary of our records of land-bird migrants for comparison with those of the party near Cape St. Vincent during the same four weeks.

Briefly, round Cape Palos we found migrants to be almost completely absent except for waders. During our stay there the only land-birds that were apparently migrants and at all common were Phylloscopi. Apart from these, we saw merely one Cuckoo Cuculus canorus, two Common Red-


starts Phonticurus phoenicuruc and up to a dozen Common Whitethroats Sylvia communis in a day.

In the Tarifa area more migrants were observed, but most of the species only in small numbers. Several raptorial species were seen in ones or twos, or up to a dozen in a day; the one exceptionally numerous species was the Honey-buzzard Pernis apivorus, about 700 of which flew southeast along the coast to Tarifa and on to Africa on 9 September and 400 more on the loth, in calm weather on both days. European Bee-eaters Merops apiaster were similarly moving southeast each day 8-1 1 September, one flock consisting of 200 birds. Of the other migrants only hirundines were numerous. Several thousand House Martins Delichon urbica moved south over Algeciras between 06.30 and 06.45 on 6 September. On the previous evening 2000 Swallows Hirundo rustica roosted on telegraph wires in Algeciras and were gone the following morning.

Otherwise migrants were scarce, only up to a dozen of any species (including Turtle Dove Streptopelia turtur and Common Redstart) being recorded on any one day. Phylloscopi and Whitethroats were remarkably scarce.

J. F. W. Bruhn.

The foregoing observations from the southeast comer of Spain and from the eastern end of the Straits of Gibraltar show a very remarkable contrast to those reported above from the southwest extremity of the peninsula during the same period. The previous records in autumn on the east coast (Alicante Province) also indicate no large passage there ; and the all-too-scanty evidence for the Gibraltar area also indicates that the narrow sea-crossing afforded by the straits is of little importance except to the big soaring birds at least uy to the middle of October, when finches begin to pass copiously (Moreau & Moreau, Ardeola ’ 1 : 3-32; 3 : 59-69). Thus it seems possible that in August and September a main beam of land-birds is directed across the Iberian Peninsula towards the southwest comer and if this is correct it is important to establish how broad that beam is. An exception to this generalization is provided by the hirundines, the scarcity of which amongst the migrants in southwestern Portugal is most remarkable. A further expedition has been organized to visit Portugal this autumn with the object of further investigating these problems.-Editor.

AUTUMN MIGRATION IN SOUTHWEST PORTUGAL, 1957

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