RSPB Medmerry 26.05.21: Little Ringed Plovers; and the decline of Herring Gulls, Linnets and Cuckoos
This post, like most of my other bird posts, includes photographs of most of the species I saw on my visit, but the text concentrates on sightings that were new to me (Little Ringed Plovers in this post), or on particularly interesting behaviours (an Oystercatcher chasing off an Carrion Crow attacking its nest). This post also explores the declines of numbers of birds we previously considered common emblematic British birds (Herring Gulls. Linnets and Cuckoos)
This was the second visit I made to RSPB Medmerry in a week; my photographs from Monday can be seen here https://www.simelliott.net/post/rspb-medmerry-24-05-21-avocet-chicks; but this was a special visit, as rather than being a solitary journey, I went with a friend who know much more about birds than me! Learning identification skills from him was a pleasure. The first time I had visited Medmerry was with this friend on 12.05.21, see https://www.simelliott.net/post/rspb-medmerry-12-05-21-a-cattle-egret-a-yellowhammer-and-a-cuckoo
The photographs in this post are in chronological order of sighting.
We saw and I photographed: Avocets, Little Ringed Plovers, Oystercatchers, Canada Geese, Cormorants, Coots, Carrion Crows, Herring Gull, Linnets, Stonechats; and a Cuckoo.
We also saw: Moorhens; Feral Pigeons; Blackbirds, Shelducks, Woodpigeons, Black-Headed Gulls, and Starlings.
We also heard but did not see: Skylarks, Wheatears, Reed Warblers; and Reed Buntings
As usual, in this post the first time I name a bird photographed I have include its scientific name (genus and species); in subsequent mentions of birds I just use its common UK name
For information on public transport to RSPB Medmerry
All text in italics are quotes, their sources are given.
We headed first to the Stilt Pools and were rewarded with views of Avocets Recurvirostra avosetta. On Monday when I had also visited Medmerry, I had seen many chicks in the northerly Stilt Pool; however there appeared to be none today.
The avocet is a distinctively-patterned black and white wader with a long up-curved beak. This Schedule 1 species is the emblem of the RSPB and symbolises the bird protection movement in the UK more than any other species. Its return in the 1940s and subsequent increase in numbers represents one of the most successful conservation and protection projects. Avocet Bird Facts | Recurvirostra Avosetta - The RSPB
However, my friend soon noticed some chicks in the more southerly pool
And he noticed a Little Ringed Plover Charadrius dubius, which we had hoped to see. Whilst they are on the green list in terms of UK conservation status the UK population is pretty small - the RSPB estimates that there are :1,200-1,300 UK breeding pairs.
The little ringed plover is a small plover with a distinctive black and white head pattern, similar to the ringed plover. It has a black beak and pale (not orange) legs. Close views reveal a distinctive yellow eye-ring. In flight, it shows a plain brown wing without the white wingbar that ringed plover has.
It first bred in the UK in 1938 and has since successfully colonised a large part of England and Wales thanks to man-made habitats such as gravel pits. It is listed as a Schedule 1 species under The Wildlife and Countryside Act. Little Ringed Plover Facts | Charadrius Dubius - The RSPB
In these photos you can see the black beak, pale legs and yellow eye ring.
Little Ringed Plover numbers are doing relatively well compared with Ringed Plovers. For some photos of Ringed Plovers (at a distance) see my post describing my visit to RSPB Pagham Harbour on 22.05.21 https://www.simelliott.net/post/rspb-pagham-harbour-22-05-21-ringed-plovers-and-dunlins
[A] new study estimated that the number of Little Ringed Plover breeding in the UK had risen by 71% between 1984 and 2007, to 1,239 pairs. The species’ core range remained in England, although breeding pairs have spread further into Wales, northern England and south and east Scotland. Gravel and sand pits were the favoured habitat for Little Ringed Plover, but its relative importance had declined compared to 1984. The species’ use of shingle habitat had grown, following range expansion into northern and western regions.
Over the same time period, the breeding population of Ringed Plover in the UK was estimated to have fallen by 37%, to 5,438 pairs. The greatest declines were reported in England and Scotland, with numbers more stable in Wales, Northern Ireland and the Isle of Man. Decreases were marked in both coastal and inland areas, including at sites where Little Ringed Plover numbers had increased. The two species have similar inland habitat preferences, so the reasons underlying the different trends are not clear. Potential factors contributing to the decline in Ringed Plover at coastal sites include disturbance from human recreational activities as well as habitat change elsewhere.
Although the UK populations of both species appear have stabilised recently, greater conservation and protection efforts are required at coastal sites to ensure local breeding numbers are prevented from dropping further. Breeding populations of Little Ringed Plover Charadrius dubius and Ringed Plover Charadrius hiaticula in the United Kingdom in 2007. Conway G.J., Austin G.E., Handschuh M., Drewitt A.L. & Burton N.H.K., January 2019 Bird Study 10.1080/00063657.2018.1563045, quoted in Breeding populations of Little Ringed Plover Charadrius dubius and Ringed Plover Charadrius hiaticula in the United Kingdom in 2007 | BTO - British Trust for Ornithology
At the back of this pool I saw an Oystercatcher Haematopus ostralegus. At first I wondered whether it was sitting on a nest; but when it stood up it wasn't.
The same Little Ringed Plover as above!
There were also Cormorants Phalacrocorax carbo at the back of this pool
Here are more photographs of the Avocet chicks; this is one brood of four chocks (although my photographs only encompass three of the chicks). On Monday I had seen two broods of chicks; both in the more northerly of the Stilt pools. Notices put up by the RSBP informed visitors that the Avocet chicks were walked by their parents form the southerly Stilt Pool to Broad Rife when they had matured a little. The Stilt Pools were "nursery" pools for the Avocets
Avocet parents, as with most birds, are very protective of their broods; at several points Avocet parents were observed warding off others birds approaching too close to their chicks.
In the mores southerly Stilt Pool there were also Canada Geese, Coots and Oystercatchers, the positions of which gave some good views of the comparative sizes of these birds.
Avocets and a Canada Goose Branta canadensis
A Coot Fulica atra, Canada Geese, a Little Ringed Plover and Avocets
Cormorants, like many long-necked birds, have extraordinarily flexible necks!
An Avocet in flight; then landing
As we looked East, over Broad Rife and the breach, we could see more Avocets, Shelducks Tadorna tadorna, Mute Swans Cygnus olor, Oystercatchers and Carrion Crows Corvus corone.
At one point we noted a tussle between an Oystercatcher and a Carrion Crow. It looked as if the Crow was trying to attack the Oystercatcher's nest, presumable to take the eggs as Carrion Crows will eat, as well as carrion, insects, worms, seeds, fruit, eggs and scraps.
after attacks and counter attacks, the Oystercatcher saw off the Crow
Oystercatchers are very protective of their nests
[This] video shows players at a Highland football game forced to dive for cover after they are buzzed by an oystercatcher. The bird was caught on camera at a match in Grantown-on-Spey and is thought to have been protecting its nest. The footage was posted online by Buckie Thistle Football Club, from Buckie, Moray, who were playing away against Strathspey Thistle. Buckie Thistle FC posted the video on their Facebook later that day saying “Bird attack. Just as well Jordan has sharp reactions.” Hilarious moment football players forced to dive for cover as oystercatcher swoops to protect nest - Deadline News
Oystercatchers call loudly to ward off potential threats to nests, as this report from the UK National Wildlife Crime Unit states: Oystercatchers are primarily shorebirds, spending much of the winter along the shoreline. Many breed inland, normally in stony fields and in areas of shingle. In some areas they have almost replaced the lapwing as the main wader nesting on farmland. They frequently nest on building sites, with their normal clutch of three eggs running the gauntlet of heavy machinery. Some birds even nest on flat roofs that have been covered with gravel. In one such case the noise made by the parents, alarmed by people walking near the house as the chicks were developing, resulted in an irate resident climbing on to the roof and throwing the chicks to the ground. Needless to say he received a visit from the police and was charged. Oystercatcher | National Wildlife Crime Unit | NWCU
There were several Little Egrets as usual; there is a Heronry at the North Wall of RSPB Pagham Harbour where Little Egrets are nesting; just a little way away.
And we saw ca. 4 Mute Swans on Broad Rife; here is one in flight. When Swans take off the flapping of their wings in flight is noisy. My friend informed me that the arrangement of wing feathers in raptors is different, making their flight silent, which is important for hunting.
A Herring Gull Larus argentatus. UK conservation status: Red. We only saw a Herring Gulls at RSPB Medmerry today. This is always seems a surprise, as they are so abundant where we live, Brighton and Hove, but this probably more accurately represents the UK conservation status of Herring Gulls, red; their numbers are in decline.
The decline in the number of Herring Gulls is anthropogenic (human-caused): over fishing and climate change (global warming)
... their breeding population has declined from 750,000 pairs in 1993 to 378,000 pairs according to the most recent figures.
The internationally important numbers of non-breeding herring gulls which spend winter here have also fallen by over 50 per cent, according to the long-term trends. Herring gulls have dropped in number at their coastal sites by 53 per cent since 1969. Despite an increase at inland nesting sites, they are still declining overall.
One of the main reasons for the decline is the lack of food for them in the coastal environment. The overfishing of UK coastal waters and warming seas caused by climate change are likely to be the main reasons for the reduced amount of food available to gulls and other seabirds.
Due to the lack of fish, the fishing fleets have also now dwindled, which has reduced the amount of fish processing waste that used to be discarded and was scavenged by gulls. Other factors include the loss of suitable coastal nesting sites, botulism and killing by humans.
Other familiar gull species that occur in the UK - such as the kittiwake, black-headed gull and lesser black-backed gull - are on the amber list, so we are concerned about them as well.
To help save our declining gull species, seabirds and other marine wildlife, we are campaigning for more protection for our marine environment. One way would be the creation of Marine Conservation Zones.
On the path we saw this beautifully strong-colour Linnet Linaria cannabina. UK conservation status: Red
The numbers of this beautiful bird are declining significantly. Linnet numbers have dropped substantially over the past few decades, with the UK population estimated to have declined by 57 per cent between 1970 and 2014. The latest Breeding Bird Survey results show a decrease in all countries. Linnet Bird Facts | Carduelis Cannabina - The RSPB
Linnet population decline is again anthropogenic; intensification of agriculture, profit before conservation, has driven the decline of the Linnet population
There is convincing evidence that nest failure rates rose during the principal period of population decline and this represents the most likely demographic mechanism driving the observed decreases in abundance. The most likely ecological driver of this pattern is habitat impoverishment due to agricultural intensification. Species | BTO - British Trust for Ornithology Woodward, I.D., Massimino, D., Hammond, M.J., Barber, L., Barimore, C., Harris, S.J., Leech, D.I., Noble, D.G., Walker, R.H., Baillie, S.R. & Robinson, R.A. (2020) BirdTrends 2020: trends in numbers, breeding success and survival for UK breeding birds. BTO Research Report 732. BTO, Thetford. www.bto.org/birdtrends
Soon after observing the Linnet we heard a Cuckoo Cuculus canorus close by, and my friend spotted it with his binoculars. UK conservation status: Red
The cuckoo is a dove-sized bird with blue grey upper parts, head and chest with dark barred white under parts. With their sleek body, long tail and pointed wings they are not unlike kestrels or sparrowhawks. Sexes are similar and the young are brown. They are summer visitors and well-known brood parasites, the females laying their eggs in the nests of other birds, especially meadow pipits, dunnocks and reed warblers. Their recent population decline makes this a Red List species. Cuckoo Bird Facts | Cuculus Canorus - The RSPB
Sadly, since the early 1980s Cuckoo numbers have dropped by 65%. Cuckoo decline | BTO - British Trust for Ornithology
The decline of Cuckoo populations has a complex causality; remaining plausible explanations for the decline of Cuckoos includes reduced prey (mainly caterpillers) availability during the breeding season or deterioration of conditions along migration routes or on over-wintering grounds in sub-Saharan Africa. Cuckoo decline | BTO - British Trust for Ornithology If the decline of Cuckoos is the result of reduced prey (caterpillars) then the decline of the Cuckoo is predominately anthropogenic; as the decline in their primary prey (caterpillars) is primarily a result of anthropogenic causes (habitat loss, pollution and climate change): The factors causing the decline of butterflies fall into three main categories: habitat loss/degradation, chemical pollution, and climate change (the latter having both positive and negative effects, depending on the species and region). The decline of butterflies in Europe: Problems, significance, and possible solutions Martin S. Warren, Dirk Maes, Chris A. M. van Swaay, Philippe Goffart, Hans Van Dyck, Nigel A. D. Bourn, Irma Wynhoff, Dan Hoare, Sam Ellis Proceedings of the National Academy of Sciences Jan 2021, 118 (2) e2002551117; DOI: 10.1073/pnas.2002551117 The decline of butterflies in Europe: Problems, significance, and possible solutions | PNAS
A submerged copse, produced as a result of realigning the coast to prevent flooding at Selsey, and establish a wetland habitat for birds. Medmeyry was created by DEFRA and the RSPB: Completed in November 2013, the multi-award winning Medmerry Managed Realignment Scheme, at Selsey in West Sussex, includes the largest realignment of open coast in the UK. 'Managed realignment' involves building new defences inland from the coast and allowing a new intertidal area to form seaward of the new defences. Medmerry Managed Realignment Scheme | Team Van Oord
A photograph from Medmerry Managed Realignment Scheme | Team Van Oord showing Medmerry shortly after it was "finished"; the former Medmerry seawall having been moved inland, a breach in the existing seas wall being made, and scrapes and culverts . The fields of oil-seed rape are now being restored to grassland by the RSPB. Grassland around wetlands are very important for ground nesting birds such as Lapwings and Oystercatchers.