24/06/13 - Exotic surprise

Following our successful goose catch in the Wheldrake corale, it’s been rather quiet with very few broods appearing in what appears to be a rather late season. However, following large numbers of Mallards breeding throughout the valley (up to 500 pairs), numbers of drakes are now starting to build up on the pool at Wheldrake to moult.

This resulted in a catch of six drakes in complete moult on Sunday, followed by six mallards (including two ducklings) and three Greylags today. However, it also turned up somewhat of a surprise - a female Mandarin!

Which is a surprise because Mandarin’s are a rather scarce visitor to the Lower Derwent Valley NNR, partly because the habitat isn’t quite right and what they would normally select, and secondly the nearest and rather small breeding population occurs about 60 km away to both the east and west. A total of 13 records exist for the Lower Derwent Valley NNR detailing 21 individuals, 18 of which are males, with the last, a male at Wheldrake Ings on the 27^th May this year. Therefore, any Mandarin in the valley is notable, particularly so a female.

The second surprise is that this bird was in complete wing moult - and looking at the stage of it, it must have been present and flightless for a couple of weeks at least. It is remarkable that it’s gone undetected on the site for this long, only to show up in one of the traps. How many other birds must slip through the valley (relatively well watched as it is) and it will be interesting to see if it is seen again over the next three or four weeks that it is likely to be present with us.

This is only the second Mandarin to be ringed in the valley following the first on 24^th April 2008 - an adult drake. Unsurprisingly there have been no recoveries of the species, although one well tracked drake in the York area did give some idea of its movements in 1983 when it was seen at Wheldrake Ings on the 27^th October and 12^th November, followed by Castle Howard lake on the 23^rd November before ‘being shot in error’ near Haxby, York, on the 26^th December.

08/06/13 - LTMN hits the road

Last week saw a flurry of activity in the Lower Derwent Valley with an influx of 30 Natural England staff and volunteers over the course of the week. This was all part of setting up the LDV as a Long Term Monitoring Network (LTMN) site. The LTMN is part of Natural England’s Integrated Monitoring Programme, which aims to provide evidence to improve our understanding of environmental change, particularly climate change, air pollution and changes in land management policy and practice. 

Rob (LTMN leader) addressing the team

A better understanding of the long-term changes will allow Natural England to advise others and to adapt our own strategies and interventions. There are currently 20 core sites in the network, which will be increased to 40 sites by the end of 2014. Most of these will be NNR's, a significant proportion of which will be those managed by Natural England.

Heading into the meadows for a long day...

 

Our task this week was to survey the 50 2x2metre permanent quadrats present on NE owned land in the valley on a host of individual sites and trying to record each species in every quadrat in addition to sward height, the amount of bare ground and extent of litter. This is the first full vegetation survey for the LDV site which will be subsequently repeated every four years to see what has changed and compare it with other information we are collecting on site such as weather, air pollution, bird and butterfly records and how the land has been managed.

LDV Team - NDC Quadrat#1 - dominated by Amphibious Bistort, Redshank, Marsh Bedstraw, Creeping Jenny and Common Bent, with the occasional Cuckoo Flower and Marsh Stitchwort.

All of those taking part in the surveys were given a half day training session on survey methods and more specific plant/grasses identification training. Obviously the Lower Derwent Valley has been chosen as an example of a lowland wet grassland site and monitoring here is likely to pick up on changes to climate in relation to flooding events, many of which featured on here strongly in the past 12 months!

LDV Team - NDC Quadrat#2 - dominated by Meadow Foxtail, Meadow Buttercup, Common Sorrel, Curled Dock and Autumn Hawkbit. 

Whilst the impacts on breeding birds have also been shown on this blog in recent posts and particularly over last summer, the LDV is also important for its range of grassland communities, ranging from the drier wet grassland types (MG4 in the National Vegetation Classification) through to swamp and reedbed (S1 in the NVC). Whilst the extent and species composition of the wetter communities appear to have remained largely unchanged over recent years, it is clear that the MG4 grassland (Meadow Foxtail and Greater Burnet communities) have been really squeezed back to the boundaries of the reserve. Hopefully the LTMN data will allow us to compare national trends on grasslands like this, as well as climatic variation elsewhere, to help unpick the real causes of any such change – national/global variation in climate or local river catchment changes, long term or just short term sporadic effects. 
 

LDV Team - NDI Quadrat#1 - dominated by Meadow Buttercup, Greater Burnet, Red Fescue, Common Bent, Red Clover, Tufted Vetch and Meadow Vetchling

Long Term Monitoring provides the baseline against which the future state of the environment can be assessed in a reliable historical context and it allows the unanticipated changes to be identified. It was also a great opportunity for a range of NE staff and volunteers to experience this NNR, share skills and get some time spent in the field with expert botanists.

 LDV Team - NDI Quadrat#2 - dominated by Glyceria and Phalaris with the occasional Marsh Horsetail and Redshank - with a Common Frog providing a welcome distraction!

It was certainly an enjoyable, if not very hot and long week, and nicely summed up by Rob Keane, Environmental Monitoring Specialist of the Integrated Monitoring Team who said ‘many thanks for allowing us to bring enjoyment and real science together on a wonderful site for all involved’.

LDV Team - East Cottingwith Quadrat#1 - dominated by Lesser Pond Sedge, Meadow Sweet, Meadow Buttercup and Marsh Bedstraw. 

Below are a selection of wildflowers taken throughout the week from various locations around the Lower Derwent Valley.   

Common Bistort

Cotton Grass

 Marsh Orchid

Ragged Robin

Cuckoo Flower

Yellow Rattle

Quaking Grass

Greater Burnet

31/05/13 - Pliers at dawn

Following a successful breeding season in the Lower Derwent Valley NNR, up to 100 Greylag goslings and 200 adults currently remain throughout the site. The largest concentration is at Wheldrake Ings, where up to 80 adults are present, accompanying 80+ goslings.

Whilst many have bred on the wetter parts of the NNR, other broods have also been walked from small ponds and other water bodies in the surrounding area away from the reserve, such as this brood seen walking along the road at Storwood before making their way across the fields and onwards towards Wheldrake Ings.

During late May and early June when the goslings are of a suitable size for ringing, the young and adults (and any non-breeding moulting and flightless adults) are rounded up using our corale trap. This involves waiting for the birds to be in the right place and herding them gently through the water and willows towards the trap. We failed to make any catch last year due to the extensive flooding so we were looking forward to this year’s catch with the hope a good sample could be marked. Things went extremely well this year with an early catch and an impressive 71 Greylag geese and a single Canada Goose were caught. This included four re-trap Greylags from previous years and an impressive 51 goslings.

This is the largest single catch of Greylags ever taken in the Lower Derwent Valley and should help our understanding of the re-established population and how birds from this population may mix with ‘wilder’ Icelandic birds which winter in the valley. The WWT are keen to increase the numbers of Greylags ringed in the country to help monitor the population and add to our knowledge so this catch is even more valuable. National ringing totals over the last five years have ranged from 300 to 678 with this catch representing 14% of the annual UK five year average total. However, it was particularly pleasing to get 51 goslings as these birds have a known age and breeding location, and with national ringing totals ranging from 52 to 81 over the last five years, this catch represents 64% against the national five year average – a great result. With a team of volunteers the birds were quickly dealt with and released to re-group into their large crèche. After the successful round up we followed it up with a brood of seven Canada Geese goslings at Bank Island.

A total of 686 Greylags have been ringed in the Lower Derwent valley NNR, producing several interesting movements, some of which are shown below, including the two longest movements of goslings ringed in the valley.

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Ringed (1) - 29/05/08 - Wheldrake Ings, North Yorkshire

Recovered (+) - 09/09/10 Caerlaverock, Dumfries & Galloway, Scotland 207 Km

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Ringed (1) - 16/06/08 - Wheldrake Ings, York, North Yorkshire

Recovered (+) - 23/09/09 - Meathop Marsh, nr Grange-Over-Sands, Cumbria 131 Km

These goslings are also getting into the regular core wintering range of Icelandic Greylags, whilst the recovery below shows an adult ringed in the winter also heading north into the main wintering area of Icelandic birds.

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Ringed (6) - 02/02/07 - Wheldrake Ings, York, North Yorkshire

Recovered (+) - 15/09/08 - Loch Leven, Tayside, Scotland 300 Km

Several goslings have also moved north-east into the Ripon/Harrogate area which has also shown an interchange of birds between the re-established and wild populations, as shown below.

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Ringed (6F) - 02/03/03 - Lingham Lake, Nosterfield, North Yorkshire

Re-sighted (VV) - 19/04/03 - Bard, Midfjordur, ICELAND 1778 Km

Re-sighted (VV) - 09/03/04 - Lingham Lake, Nosterfield, North Yorkshire

Re-sighted (VV) - 21/01/05 - Castle Howard, North Yorkshire

Re-sighted (VV) - 11/02/05 - Castle Howard, North Yorkshire

Re-sighted (VV) - 19/02/05 - Lower Derwent Valley NNR

Greylag Geese in the Lower Derwent Valley provide a classic example of both how a species status can change in a relatively short period of time and through increased knowledge of ecology and movements. The species was a rarity to the Lower Derwent in the 1970’s with a mere five birds recorded during 1974. Since 1976 they have been recorded annually, followed by resident status first achieved in 1979 with a record count of 44 present in the December of that year. Numbers increased quickly to peaks of 110 in 1980 and 200+ in 1981 to 560 in 1988. In 1993 numbers reached 820 but over recent years (since 2000) counts of 2000+ are not unusual. Breeding numbers have increased likewise with the first breeding pair in 1978 increasing to ten pairs the following year and 25 pairs by 1986. Numbers of breeding pairs in and around the valley now typically average 40-60 pairs.

Following the goose catch a brood of four Jackdaws plus the adult bird were then caught from an Ash tree at Bank Island. This tree has been a regular nest hole for many years for a number of species including Barn and Tawny Owls, however Jackdaws have now been in residence for the last ten years and the owls have moved off to the nearby boxes.