Ruddy Shelduck
Tadorna ferruginea
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BOU Category:
Site status: Devon status: Conservation status: Conservation levels: |
BDE* (GB),
DE (site)
† vagrant escapee Cat E † †, alternatively, ‘Rare vagrant or feral visitor/escapee (all records assumed the latter) † BOCC3 (unlisted)†; SPEC (3); IUCN European (Vulnerable); Global (Least Concern) † n/a |
International
Migrant populations arrive Apr/ May on open steppe and upland plateaux to nest often far from water although generally found on rivers and lakes; tends to avoid coasts. A long distance dispersal migrant to post-breeding moult congregations, when flightless for a time within the period mid-Jul to Sep, then later moving onto wintering grounds†.
Europe
In the 19th century, sporadic irruptive late-summer movements recorded, exceptionally as far NW as W Greenland, most notably in 1892. Up to the 1950s, a few hundred wintered in S Spain from NW Africa population, but has since declined and it is now considered a rarity in Iberia††.
Escapees from collections and deliberate releases, particularly the 1950s - 1990s, led to widespread, sporadic, but mostly non-sustaining feral breeding in Europe. A few pairs regularly breed in Belgium, The Netherlands, France, Poland, Denmark and Germany (where, ambiguously, 5 - 60 pairs were reported)††. However, the Swiss feral population (first bred in 1963) rose to c.450 individuals in late-summer 2004, before being virtually eradicated through targeted action†. The Dutch Delta winter count up to 150 individuals † and a flock of c.50 birds present in 1995/96 suggest feral establishment††. The feral population at Askaniya Nova Biosphere Reserve, Ukraine comprised of some 300 pairs in 1994†, but the situation is complicated by feral birds intermixing with nearby wild populations and wintering wild birds.
Great Britain
Introduced onto ornamental waters from the 19th century, tens of
birds are thought to be at large in the wild and one or two pairs
occasionally breed, with a maximum of 3 - 5 pairs in 2005†.
Reviews of its status in 1982, 1999 and 2002 have attempted to identify the source of records in GB. The first review concluded that despite the spring and autumn bias, all pre-1892 records and all post-1950 records were considered of captive origin. It examined 75 reports of 123 individuals (excluding a free-flying flock in York) during the 1965 - 1979 study period; most were singles, the largest flock size was eight† .
The 1999 study focussed on the invasion (a maximum of 406 birds in Fenno-Scandia and NW Europe) in late-summer 1994, examining GB records at that time in the context of records during the period 1986 - 1994. Annual counts ranged 23 - 62, and although 55 individuals in 1994 were unexceptional, one text concluded that although many records, “are attributable to escapes from captivity and their descendants, the pattern of occurrence…strongly suggest that wild birds are involved.” However, an alternative view was that the 1994 invasion could be solely attributable to dispersal of most of the feral population at Askaniya Nova, Ukraine, due to severe drought. Drought was also speculated as a possible factor accounting for several notable flocks in GB during 1992 & 1993†.
In 2002, records were reviewed again, concluding that, “The probability that records of this species relate to individuals of feral or captive origin is very high, yet vagrancy remains possible…” †.
Given the proximity of the rapidly expanding natural population in SW Asia and that Askaniya Nova may also support wild birds†, past conclusions may all be correct to a degree, in that records in 1994 involved resident wandering escapees and an irruptive movement of self-sustaining feral birds and wild birds from Asia.
Following the latest review, the species was retained on Cat B on account of the 1892 invasion only (which saw flocks of up to 20 birds in many places)† Some subsequent, sightings, including seven records 1961 - 1966, † are only elevated to Cat D status†.
Devon
Unable to find supporting descriptions, the record of 3 birds shot
in either Jun at Braunton or in Sep 1892 at Woolacombe Sands, could
not be accepted by BBRC, despite being during the largest ever
recorded irruption of wild birds in GB†.
Therefore this species is not included in the official Devon list†.
Reported annually since 1984 (except 1993), mostly involving 2 - 7 birds as singles. Pre-1994, four on Otter Estuary Jul/ Aug 1992 was an intriguing record. The 1994 invasion to NW Europe & Britain also saw arrivals in Devon. A flock on the Hayle in Oct occasionally commuted E as far as the Tamar (five on 28 Nov), with three on Chelson Meadows, Plymouth and Slapton in late-Dec††. An individual that first appeared at Passage House Inn, Teign Estuary on 22 Jan 1995 generated much interest amongst birders, not least due to following the 1994 invasion, although subsequently returned to winter at the same location 1995/96 - 1997/98.
Perhaps one in 1999, but certainly four in the Torbay area from Aug/ Sep 2000 were escapees from Paignton Zoo (contra Tyler, 2010); also present in 2001, with three in 2002/03, then one or two still present into 2010. Although these individuals wandered, e.g. to Bowling Green Marsh, up to 3 additional escapees were annually reported elsewhere around Devon.
Although eight on R. Dart (Mar) was possibly erroneous, 2003 also saw a flock of five coasting from Dorset to Exminster Marshes (Oct), see below†.
Dawlish Warren
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There are five records involving nine birds: |
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| 29 Nov 1986 | one (A Mears) |
| 05 Aug 1993 | one flew down the estuary then up Shutterton Creek (C Coombes) |
| 09 & 11 Jul 1995 | one in the Railway Saltmarsh (anon, KRy) |
| 18 Jul 2000 | one (DWL) |
| 07 Oct 2003 | five; in off sea (JEF, DJw). Seen earlier that day off Chesil Beach, Dorset and later on Exminster Marshes |
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Updated 31/08/2013