Second Records of the Caspian Tern Hydroprogne caspia in Lebanon 2022

Mini Review

Caspian Tern Hydroprogne caspia is a monotypic, cosmopolitan species occurring in North America, North Europe, Africa, Madagascar, Asia, Australia, and New Zealan [1, 2]. There are only three European populations of approximately 4,500 breeding pairs along the coasts of the Caspian, Black, and Baltic Seas [3, 4]. It’s the largest of the terns, with a wingspan averaging. It has a body length of 48 - 56 cm, a weight of 570-780 gram and a wing span of 127- 140 cm. Its size, stout red bill, and lack of a deeply forked tail distinguishes it from other white terns found in the state. Its black cap, large red bill, and tern-like habit of flying slowly with its bill pointed downward separates it from the gulls. The low harsh call of the Caspian tern sounds similar to karrr or kraa-ah and is given frequently while in flight. The orange feet of immature birds distinguish them from fall-plumaged adults which have black feet [5].

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (extent of occurrence <20,000 km2  combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be increasing, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern [6].

Breeding almost worldwide in geographically isolated populations, in Europe Caspian Terns also have distinctly disjunct breeding areas. The larger breeding colonies are concentrated in the north Caspian (the Volga Delta, 3000- 5500 pairs in 1984-1988) and 250-800 pairs along the northern coast of the Black Sea (Heath et al. 2000. Apart from 2-3 small colonies in Turkey (totalling about 300 pairs) the only other population of importance in Europe breeds in the Baltic. In Finland, Sweden and Estonia, some 1500-1600 pairs were present in the 1990s and early 2000s [7, 8].

Contrary to most other tern species, Caspian Terns routinely fly overland in Europe and in Africa on their way to and from their wintering quarters.

When foraging flies high over water, hovers, then plunges to catch fish below surface. Less often flies low, dips down to catch prey at water’s surface. May steal food from other birds.

Its diet consists predominantly of fish 5-25 cm in length also including the eggs and young of other birds, carrion, aquatic invertebrates (e.g. crayfish), flying insects and earthworms.

On the 15th of September 2021, and during a birdwatching trip in Cheikh Zennad, Akkar District in North Lebanon, I spotted 2 Terns (Figure 1) coming from the north over the sea and passed through the land heading south during the Fall migration. Then, on the 18th of January 2022, I was able to identify another individual (Figure 2) on the seashore in Al Mina, Tripoli District, north Lebanon while I was birdwatching with my friend, a birdwatcher too, Pascal Azar. It was fishing among some Yellow-legged Gulls and Black- headed Gulls that were stealing his food (Figure 3). The bird stayed for 4 hours there and then it left the area heading toward the Palms Island. I was able to confirm the ID and add it officially to the Lebanese National Bird Checklist as the second record of the Caspian Tern in Lebanon.

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