Whilst work may be birding related, it is rare that I do anything I would consider as birding for work. For once, though, we were contracted to do something different - monitor the breeding success of Black-tailed Godwits at on the River Ribble in Lancashire. Seen as everyone at work was already busy, I took it upon myself to get involved and visited every couple of days for a few weeks in May and June 2019.
Two sub-species of black-tailed godwits
regularly occur in the UK: L.limosa and
L.l.islandica. The limosa
subspecies breeds on the Ribble and a handful of other sites in England, with the
majority of the UK population in the Cambridgeshire Fens. The breeding
population is approximately 60 pairs annually, and it is therefore one of the
rarest breeding birds in the country.
Considerable conservation measures are on-going to safeguard the species and
its breeding habitats in the Fens, including habitat creation and a
‘head-starting’ breeding programme (using artificial incubation and protecting
the chicks during the rearing period so as to increase breeding productivity
and boost numbers).
The Icelandic islandica subspecies also occurs regularly in the UK, with large numbers using estuaries and wetlands around the country
throughout the year. A smaller number of the islandica subspecies also breed annually in Orkney and Shetland.
Godwits were first recorded breeding on the Ribble in 1984 and have attempted most years since. Typically just one pair is present, but in some years two pairs attempt, and this is the sole location in the north of England. Breeding success is sporadic, so the tiny population is highly vulnerable.
Two pairs attempted to nest in 2019. An additional
(unpaired) bird was also present throughout the breeding season, and it was a real pleasure to observe them.
Small numbers of non-breeding islandica birds were also regularly present, using the central drainage ditch to feed and roost. Interaction between the breeding and non-breeding birds was never noted.
'Pair A’ had two chicks, first seen by Paul Ellis on 25th May and with the last observation on 18th
June. The sudden disappearance of the birds, with the adults being seen subsequently in distressed state,
strongly suggests that the chicks perished at around 25 days old. At this age
the chicks were probably within no more than a week of fledging (flight
capability) and therefore relatively large. A real shame, we were almost there!
‘Pair B’ had a single chick,
which I first observed on 29th May, and it was clearly smaller than the Pair A chicks
(therefore younger). This chick was last observed on 1st June and
was presumably predated. The pair lingered around the marsh for a few days after
the chick disappeared.
A single (unpaired) bird was present throughout.
It was assumed to be a male by a combination of behaviour (regular display
flights) and plumage (pale faced). It regularly showed aggression towards
predators and also Pair A and Pair B.
It's rare I get the opportunity to watch bird behaviour like this and it was a thoroughly enjoyable summer in that respect, despite the sad outcome. It was a real privilege and for once I spent some time away from the desk. I had not previously realised how structurally distinct Limosa birds are, and as ever once I started watching them I realised how little I knew about the species.
As well as the godwits, the marsh supported breeding Shoveler, Avocet, Little Ringed Plovers and good populations of Lapwing and Redshanks. A great place to linger, although a prolonged period of heavy rain in June seemed to decimate populations of all waders.
Predation is the major issue though, mainly down to poor landscape management which has included planting of trees and hedgerows which in turn support breeding buzzards and crows.
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