Category Archives: Field Notes

On the Griffon that swam across the Strait of Gibraltar…Check this video out!

Immature Griffon reaching the European continent from Africa after crossing the Strait of Gibraltar

Under suboptimal weather conditions, like strong crosswind and rain showers, the narrow sea crossing that separates Africa from Europe at the Strait of Gibraltar may present a major obstacle to migrating raptors. This is particularly true for the Eurasian Griffon, the largest soaring migrant in the area. In fact, the mere 14.5 Km that separate both continents is at times an insurmountable barrier, causing an undetermined number of vultures to fall into the sea every spring.

Once in the water, Griffons show an impressive instinct of survival and use their large wings as paddles in a desperate attempt to reach the shore. Except in the rare occasions when fallen Griffons are rescued by passing vessels, their fate is normally fatal. This is a highly dramatic scene and a brutal example on the forces of natural selection that we observe every spring in the Strait of Gibraltar.

Immature Griffon in active migration across the Strait of Gibraltar, with Europa Point (Gibraltar) in the background.

But! Last 1st of May we witnessed the absolutely exceptional and unbelievable case shown in the following video:

With moderate westerly winds a group of 36 Griffons undertook the sea-crossing of the Strait from the Djebel Mousaa in Morocco to Punta Carnero in Spain. As they approached the European shore, we saw the kettle soaring in a thermal updraft over the Ocean. This is a rather infrequent event as thermal updrafts do rarely occur over water bodies. Nonetheless, the thermal seemed to suddenly dissipate and vultures did rapidly lose height. In a strenuous active flight, most individuals managed to safely reach the continent. Two vultures, however, did not have the strength to go on and hit the water!

Their efforts to stay afloat an reach the shore “swimming” where hampered by the ruthless attack of Yellow-legged Gulls and had us on tenterhooks for over 15 minutes. We finally saw one of them drowning while, to our surprise, one of them skilfully reached a rocky islet near the shore! After some 45 good minutes spreading its wings to the sun in a cormorant fashion, and boosted by a timely gust of wind, the vulture took off again and completed the intercontinental flight causing cheers and applause from all present observers!

It is indeed because of this kind of observations that we will never have enough of raptor migration in the Strait of Gibraltar!

The Honey Buzzard Big Day

Adult female Honey Buzzard in active spring migration across the Strait of Gibraltar.

In early May Honey Buzzards play the leading role in the raptor migration in the Strait of Gibraltar. This is, no doubt, among the most celebrated and awaited periods for international birders and nature enthusiast visiting Tarifa. Thousands of this otherwise rather secretive and forest-dwelling raptors will cross the ocean between Africa and Europe in massive streams. Crosswind direction, westerlies vs easterlies, will determine the flyway, which may range from the Rock of Gibraltar to Sierra de La Plata and beyond.

Adult Honey Buzzard crossing the ocen in a misty day in Tarifa.

The first big groups of migrant Honey Buzzards where observed last 2nd of May in the Eastern side of the Strait. Tomorrow, 5th of May, we expect a BIG DAY in the Tarifa area prompted by a shift in the wind direction. Indeed, the bulk of the Western European breeding population of Honey Buzzards will cross the Strait within the ongoing fortnight. The strength and determination while on active migration of these apparently delicate raptors is admirable. The spectacle is greatly enhanced by the striking diversity in their plumage colour. Indeed Honey Buzzards shows the most striking colour polymorphism among European raptors (with all due respect from Common Buzzard). This way, some individuals show a paler-than-an-Osprey plumage, while others look completely black.

Dark morph adult male Honey buzzard in actibe migration at low height in the Strait of Gibraltar.

Remarkably, only adults will cross the Strait during spring and juveniles (born in 2017) will extend their stance south of the Sahara until next spring.

Do not miss this animation, based on satellite tracking from the University of Amsterdam showing the 3D migration route of Dutch Honey Buzzard to Africa and back across the Strait of Gibraltar.

Pale adult male Honey Buzzard with notably worn primaries in active spring migration in the Strait of Gibraltar.

As every year, Birding The Stait will be in the frontline to admire this natural wonder. We cannot think of a better way to celebrate the Global Big Day!

Spring has begun! 6 birding hotspots to check out in Tarifa and the Strait of Gibraltar

Adult Purple Heron at La Janda.

Spring has just begun! As temperatures warm up, we are reminded how good birding can be during a visit to the Strait of Gibraltar in Spring. To give you an idea of what’s possible to see during this season, here we list some suggestions about what to do in a day, and what you should expect to see:

Lesser Kestrels can be easily seen around Tarifa, as they start their breeding season
Lesser Kestrels can be easily seen around Tarifa, as they start their breeding season

1. An early start in Tarifa, where we are based, can be rewarded with the prominent song of the Common Bulbul, a common species in Africa that, however, can only be found in one location in Europe: Tarifa. Nearby, we’d probably hear the sharp calls of the Lesser Kestrels too. At a walking distance, a short session of seawatching from the pier can provide good views of migrant seabirds, like Northern Gannet, Razorbill, Atlantic Puffin, Arctic Skua (Parasitic Jaeger) and the first Balearic Shearwaters coming out of the Mediterranean after their breeding season.

Western Yellow Wagtail, from subspecies iberiae, also known as Spanish Wagtail
Western Yellow Wagtail, from subspecies iberiae, also known as Spanish Wagtail

2. As you drive out of Tarifa, it might be a good idea to make a stop in Los Lances. This small nature reserve can be very productive, particularly in the morning. Mediterranean and Audouin’s Gulls are regular at this time of the year, same as Kentish Plovers. The migration of passerines can be visible here, with the first Western Yellow Wagtails and Greater Short-toed Larks showing up, while the last Meadow and Water Pipits abandon these latitudes in order to breed further north.

The Rock Bunting is an uncommon but regular species at Sierra de la Plata
The Rock Bunting is an uncommon but regular species at Sierra de la Plata

3. A visit to the lower limestone ridges around Tarifa, like Sierra de la Plata can be very good. Some species you should expect, and already singing in their breeding plumage, can be: Cirl and Rock Buntings, Iberian Green Woodpecker and the gorgeous Blue Rock Thrush. On top of that, the Eurasian Griffons will already be on their nests, some of the hatchlings already out of their shells. Surely, we will be looking for the first Black-eared Wheatears of the year, as well as the passing Northern Wheatears.

Eurasian Sparrowhawk as its arrival to the European Continent
Eurasian Sparrowhawk as its arrival to the European Continent

4. Depending on the winds, we will be sure to be well positioned in order to witness the raptor migration that takes place, roughly, from March to May. Even though many raptors have already passed by the beginning of Spring, there are still thousands still waiting for their opportunity on African soil: Short-toed Eagles, Booted Eagles, Black Kites, Sparrowhawks, Egyptian Vultures as well as good numbers of White and Black Storks. One of the best places to see these birds crossing the Strait would be Punta Carnero, not far from the city of Algeciras.

Northern Bald Ibis starting their breeding season at the colony
Northern Bald Ibis starting their breeding season at the colony

5. After having lunch at one of the numerous excellent restaurants that serve homemade food in the area, we can visit the Northern Bald Ibis colony, a must-see species for every birder, and certainly a highlight for anyone traveling to the province of Cadiz. This can be combined with a visit to the Barbate Marshes, which can be very rewarding, both for shorebirds and migrant passerines.

Corn Bunting: a common song in the fields of La Janda
Corn Bunting: a common song in the fields of La Janda

6. An excursion to the southernmost region of Spain can not be complete without a drive through La Janda. This well-known birding hotspot is excellent throughout the year, but even more splendorous during the spring months. The beginning of the season seems to be marked by the hundreds of Garganeys, which can be seen flying along the shoreline. However, if the weather has been wet enough and some of the seasonal lagoons and rice paddies are flooded, good numbers of these gorgeous dabbling ducks can be seen in La Janda. Along with the ducks, Purple Herons start to arrive, and Hoopoes are easier to find while feeding along the tracks. Raptors are always abundant here, and among all of them the Spanish Imperial Eagle stands out, due to its large size, on average almost as large as a Golden Eagle.

All of this is possible in a day without needing to drive very long distances, while you enjoy the spectacular scenery of the Strait and experience the marvels of migration firsthand. With the possibility of including other bird-rich locations or adapt the itinerary for wildlife photographers, the combinations are endless! If you want us to arrange a private excursion for you to see  some of these sites and find some of the most sought after species of birds, contact us and let us know what your preferences are. You will find out, the Strait of Gibraltar never disappoints!

MIGBird Tarifa 2018, welcome to migratory birds!

MIGBird Tarifa 2018 “Welcome to migratory birds” starts tomorrow, March 19th, at the Cazalla Bird Observatory! Birding The Strait will be opening the event with the first presentation at 10:00. An extensive programme of excursions, educational activities for children, photo exhibitions and a bird race have been organized and coordinated by the Tarifa Town Hall in collaboration with local companies and NGOs. Within the event, next Sunday 25th we will be offering a free guided visit to the Isla de Las Palomas, a restricted area of El Estrecho Natural Park in the southernmost tip of the continent and an excellent site for seawacthing!

Iberian Lynx on the spot

The fur of the Iberian Lynx shows a striking variation ranging from thickly spotted orangey phenotypes to rather stripped greyish individuals, including a wide range of intermediates. As a result of the dramatic decline that the species suffered during the previous century, some fur variations disappeared from certain populations. In Doñana, for instance, only thick-spotted Lynxes occurred from the 60s (source Life+IBERLINCE).

Navajuncosa is a female of the Thick-spotted type born in Córdoba in 2016. She takes her name from one of the estates where actions to improve the habitat for the Lynx have been undertaken. This picture was obtained from a wildlife photography hide fullfilling all legal requirements aplicable. January 2018.

Nowadays, the phenotypic diversity of the Iberian Lynx is recovering its former splendour thanks to translocations and population reinforcements by means of captive breeding. This phenomenon should be understood as a visual statement of the undergoing population recovery, now totalling over 500 individuals in Spain and Portugal (less than 100 by the early 2000s).

This winter we have guided several tours with the Iberian Lynx as  main target and, luckily enough, we have had the chance to observe all the most representative fur types (!).

A male Lynx scans his territory in Andujar lying atop a “bolo” granite formation, characteristic landmark in Sierra Morena, Jaén. December  2017.

In doing so we closely collaborate with renowned local guides and companies to ensure our clients the most respectful approach to this and other sensitive species. Here, we wish to echo the recently published “Guide for responsible Iberian Lynx watching” by Life+IBERLINCE project.

In Birding The Strait, we strongly believe in ecotourism as a sustainable activity which benefits nature conservation and local economies and we enthusiastically work to make this true with our Iberian Lynx experiences.

Drop us an email if you want to join us in one of our scheduled Iberian Lynx Quests!

Everything you wanted to know on the Booted Eagle migration and never dared to ask!

Dark morph Booted Eagle reaching Europe from Africa across the Strait of Gibraltar.

The Booted Eagle is one of the most representative species of the raptor migration in the Strait of Gibraltar. It is a medium sized raptor of powerful flight whose migration has received low attention by the scientific community. This has changed, however, with the recent publication of a comprehensive monograph on the “Migration and spatial ecology of the Spanish population of the Booted Eagle” based on GPS tracking. The work has been conducted within the MIGRA project of SEO/Birdlife and has had the input of a remarkable group of ornithologists from different Spanish institutions. The results have been presented in a beautifully edited open access document in Spanish with English summary.

Booted Eagle in active migration over the ocean in Tarifa.

Birding The Strait has contributed to this project with several photos of Booted Eagles on migration in the Strait of Gibraltar, including the one in the cover. As ornithologist and birdguides in Tarifa we have received this publication with big interest and next we summarize some of the most striking results:

Pale morph Booted Eagle over Tarifa in southbound migration to Africa.

In Spain the Booted Eagle is a migrant species except in the Balearic Islands, where it is resident. Booted Eagles spend 13% of their lives on migration, 42% in their breeding grounds in Europe and 45% on their wintering quarters in Africa.

All migratory routes converge in the Strait of Gibraltar where the average date of arrival is the 17 of September and the 31st of March in their Southbound and Northbound migrations, respectively. Eagles crossed the Sahara in a broad front following similar routes in spring and summer, with no coastal flyways observed. The studied individuals completed their migration in 28 in spring and 23 days in autumn. Interestingly, this pattern opposes the general trend observed in most migratory species, on which the return migration to their breeding grounds is faster than the autumn migration to the wintering quarters. The eagles flew an average of 8 hours a day, covering from 130 to 250 km, with an absolute record of 541km between two consecutive night roosts!

Dark morph Booted Eagle in the Strait of Gibraltar.

Visual counts in the Tarifa area have shown that approximately 71% of the individuals belong to the pale morph while 29% belong to the dark one.

The number of Booted Eagles crossing the Strait has significantly increased within the period 1999-2016 and a similar result has been obtained at raptor watchpoints in the Pyrenees. Nowadays over 30.000 Booted Eagles cross the Strait of Gibraltar to Africa every year.

The bulk of the Iberian population overwinters in the Western Sahel region including Mauritania, Guinea, Mali, Burkina Faso, Niger, Nigeria, Chad, Cameron and Sierra Leona with a remarkable wintering site fidelity in consecutive years.

Pale morph Booted Eagle in Tarifa.

The number of Booted Eagles overwintering in Spain is steadily increasing over the last decades and nowadays it should be considered a scarce but regular wintering species. We recommend to consult eBird to get further insight on the wintering population of Booted Eagles in Spain.

Juvenile pale morph Booted Eagle perched in a powerline which has been isolated to avoid raptor electrocution in La Janda, the Strait of Gibraltar.

The logo of a leading energetic corporation on the front cover may arguably raise alarm bells to critical readers. In fact, Iberdrola has been sanctioned with millionaire euro fines in Spain on account of the electrocution of raptors, including the endangered Spanish Imperial Eagle. Pushing conflicting emotions aside, it is important to highlight that this work identifies and highlights electrocutions and hunting as the two main causes of non-natural mortality for the species.

Pale morph Booted Eagle in active migration in the Strait of Gibraltar.

The global results show the Booted Eagle as a rather plastic species on its foraging, migrating and habitat selection habits with a wide distribution range. It seems likely therefore that thanks to this attributes the Booted Eagle will have a more promising future than other less adaptable species. This work stresses the importance of stablishing integrative conservation measurements including its breeding sites, foraging areas, migration flyways and wintering regions.

Booted Eagle near Tarifa
Booted Eagle in active migration near Tarifa

All in all this work fills an important gap on the knowledge of raptor migration and it is of interest for bird enthusiasts, researchers and decision makers.