The black geese of the genus Branta are waterfowl belonging to the true geese and swans subfamily Anserinae. They occur in the northern coastal regions of the Palearctic and all over North America, migrating to more southernly coasts in winter, and as resident birds in the Hawaiian Islands. Alone in the Southern Hemisphere, a self-sustaining feral population derived from introduced birds of one species is also found in New Zealand. one species has been described from subfossil remains found in the Hawaiian Islands, where it became extinct in prehistoric times. Another undescribed prehistoric species from the Big Island of Hawaii was extremely large and flightless; it is tentatively assigned to this genus due to being very peculiar. It is fairly certain that at least another species of this genus awaits discovery on the Big Island, judging from the facts that at least one species of Branta was found on every major Hawaiian island, and that remains of such birds have not been intentionally searched for on the Big IslandThe relationships of the enigmatic Geochen rhuax to this genus are unresolved. It was another prehistoric Big Island form and remains known only from some parts of a single bird’s skeleton, which were much damaged because the bird apparently died in a volcanic eruption, with the bones being found in an ash-filled depression under a lava flow. A presumed relation to the shelducks proposed by Lester Short in 1970 was generally considered highly unlikely due to that group’s biogeography, but more recently, bones of a shelduck-like bird have been found on Kauai. Whether this latter anatid was indeed a shelduck is presently undetermined. Several fossil species of Branta have been described. Since the true geese are hardly distinguishable by anatomical features, the allocation of these to this genus is somewhat uncertain. A number of supposed prehistoric grey geese have been described from North America, partially from the same sites as species assigned to Branta. Whether these are correctly assigned, meaning that the genus Anser was once much more widespread than today and that it coexisted with Branta in freshwater habitat which it today does only most rarely, is not clear. Especially in the case of B. dickeyi and B. howardae, doubts have been expressed about its correct generic assignment
Listen to the sound of Red-breasted Goose
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On the western Black Sea coast, the winter feeding habitat comprises agricultural land dominated by cereal crops and grassland. The birds periodically fly to coastal lakes to drink. These lakes, situated up to 50 km from the feeding areas, are also safe night-roosts. The proximity of drinking and roosting sites to feeding areas may influence winter distribution. In Bulgaria, Red-breasted Geese roost on water; usually in the middle of lakes, but occasionally, or in times of high hunting pressure, on the sea if it is calm. When the lakes freeze (which is rare) they roost on the ice. Roost sites in Romania are in remote parts of wetlands where the geese utilise shallow water, and muddy and sandy beaches with low aquatic vegetation. On the Evros delta in Greece, the Red-breasted Goose feeds, and possibly roosts, on a specific area of natural vegetation.
Red-breasted Geese arrive on the breeding grounds in early June, around the time that the snow on the tundra melts. They nest in colonies averaging five to six pairs. Laying begins in the second half of June and the clutch contains 3-10 eggs, most commonly 4-5. Incubation lasts 25 days and the fledging period 5-6 weeks. Clutch loss is usually less than 15-20%. Breeding success fluctuates from year to year and depends mainly on the birds’ condition when they arrive on the breeding grounds, as well as on climate, predation and population levels of birds of prey. Severe climatic conditions can inhibit all recruitment. The arctic fox is the main predator, the degree of predation depending largely on the cyclical variation in abundance of the fox’s main prey, the lemming, and on the proximity of nests to those of Peregrines, Rough-legged Buzzards Buteo lagopus and gulls which are thought to impart protection from the fox. Observations showed a correlation between the presence of nests of these birds and the average number of nests of Red-breasted Geese.
Video Red-breasted Goose
This species is breeding in the tundra of northern Russia, more precisely on the Taymyr, Gydan and Yamal peninsulas. It used to winter in large numbers South of the Caspian Sea, and was known from Egypt and Iraq. Since the 1940’s and 1950’s it has shifted its winter quarters to south-eastern Europe, however, mainly to Romania and Bulgaria. It also appears irregularly and in small numbers in Hungary, Greece and Turkey. Its global population amounts to about 70000 individuals, but only a few dozens or hundreds of birds (maximum 2000) are visiting the European Union, particularly northern Greece. Following the strong decline in the wintering areas South of the Caspian Sea the species was considered as endangered, but the discovery of large wintering populations in Romania makes this conclusion unlikely or exaggerated. In fact the actual trends of this species are still unknown. The reasons are explained below.
It has been difficult to monitor changes in Red-breasted Goose numbers as the birds range across a wide wintering area (c.1,200,000 km2) and counts have been infrequent. The maximum population estimates and counts (where available) for each year since 1899 are given in Annex 2. Prior to 1954, records were scarce, but it is thought that numbers were larger than, or similar to, those of today. In 1899 “many tens of thousands of Red-breasted Geese were seen in their wintering sites” (Krivenko 1983). Between 1956 and 1967 numbers were estimated at c.50,000-60,000; the best coverage was achieved in the winters of 1967 and 1968 when a total of 49,000 was counted in the Black and Caspian Sea regions, divided equally between the two. Between 1969 and 1989 count totals did not exceed 30,000, and ornithologists suggested that the population might have crashed due to the birds being forced from their traditional wintering area on the Caspian Sea and/or the effects of DDT on Peregrines Falco peregrinus which protect nesting geese from arctic foxes Alopex lagopus. Recent counts, which included coverage throughout the Black Sea wintering range, gave population estimates of 70,000-74,000 in three consecutive years. However, the overall count for 1993/94 was only 37,400, in spite of near-optimum count coverage (excluding the Caspian region), illustrating the erratic nature of population estimates.
The 1991-1993 counts indicate, therefore, either that the population doubled in size in just a few years (i.e. from 25,000 in 1989 to 70,000 in 1991) or, more likely, that significant proportions of the population were not recorded in previous years, especially in the late 1980s. Indications from other, well studied, goose populations (Owen and Black 1990) suggest that the former hypothesis is unlikely. It is also possible, therefore, that the apparent decline in the Red-breasted Goose population in the 1970s may have been much less dramatic.
The apparent increase in Red-breasted Goose numbers may be due to improved monitoring, but as information is limited it may also be the result of improved conservation in both the breeding and wintering ranges and/or possibly the recovery of populations of birds of prey. Recent world population estimates are 70,000 to 74,000.
In early May the birds reach the Kazakh uplands and by early June have reached the breeding grounds. Autumn migration starts in mid-September, birds reaching Kazakhstan by the end of September. A few may continue south to the Aral Sea, while the majority travel south-west towards the Caspian. Small flocks may remain to winter on the Caspian Sea coast in Azerbaijan and some individuals continue south to Iran and Iraq. The majority, however, travel on to the western Black Sea coast, arriving in October-November and are usually found with White-fronted Geese Anser albifrons. Small numbers may visit Greece from the main winter quarters in Bulgaria and Romania.
Prior to 1950, the main wintering areas were the southern coasts of the Caspian Sea, particularly the south-west coast. In 1968, counts indicated that about half the wintering population shifted to the west coast of the Black Sea (Annex 2) which is c.1,800 km west of the Caspian. In the 1970s, very few Red-breasted Geese were found on the traditional sites on the Caspian, presumably because of reduced food availability and hunting pressure. Scattered records of small flocks further south may indicate that the birds ranged much further before monitoring began. The earliest known records of Red-breasted Geese are from Egyptian friezes c.6,000 years old, perhaps suggesting that they were once frequent visitors to that area.
The current wintering areas on the Black Sea coast are the Shabla and Durankulak lakes of Bulgaria, the lagoon/steppe complex of the Danube delta in Romania, and the Dobrodgea plateau which lies between the Danube and the coast and spans the Bulgaria/Romania border. In recent winters, 80-90% of the world population of Red-breasted Geese wintered in Bulgaria. Small flocks winter in the Ukraine and possibly Azerbaijan while others may visit Greece. Occasionally very small numbers reach Hungary, Turkey, Iraq and Iran. The species is accidental in the United Kingdom, Belgium, Netherlands, Norway, Sweden, Denmark, Finland, Germany, France, Poland, Czech Republic, Slovakia, Austria, Italy, Spain, Albania, Serbia, Israel, Cyprus, Egypt and south-east China.