August 2015: Rye Harbour Nature Reserve Sightings

It’s not very often that we get to add a new species of mammal to the reserve list, but we did manage it this month with the discovery of Nathusius’ pipistrelle at Castle Water on the 27^th. Eleven bats were trapped under licence using a combination of sound lures and ‘harp traps’ the largest number of individuals ever caught in a single night in the UK. Though rarely recorded, this species has a wide distribution, with records as far north as Shetland (the site of the first UK record in 1940) to the south coast. A migratory species in Europe. it was initially considered to be only an accidental visitor to the UK, though since then research has suggested that there may be regular migration between the UK and Scandinavia in Spring and Autumn, with some individuals remaining all year, and it is now a breeding species.

An increase in passage movement later in the month saw a good range of waders on the reserve. These included increasing numbers of lapwing, with 1000 at Castle Water on the 14^th and 20^th, 71 golden plover (above) on Flat Beach Level on the 29^th, regular common sandpiper and small numbers of black-tailed and bar-tailed godwit, avocet, ruff and whimbrel. Highlights were 11 wood sandpiper 18 green sandpiper and 44 greenshank on Flat Beach and nine curlew sandpiper on Harbour Farm downed by poor weather on the 24^th, and at least one little stint and another curlew sandpiper on Flat Beach on the 30^th. Passerines also showed evidence of passage movement. Hirundines included up to 270 sand martin, 200 swallow and 60 house martin during the second half of the month, while 250 swift were seen on the 24^th. Large numbers of yellow wagtail on the Beach Reserve late in the month peaked at 350 on the 24^th, with 14 wheatear on the 29^th. In addition, linnet numbers have been increasing as we move towards autumn with around 250 present on the Beach Reserve on the 15th, with 400 starling also here on the same date. Other notable avian sightings during the month included two hobby at Castle Water on the 14^th, two peregrine over the Beach Reserve on the 21^st and a garganey at Castle Water on the 30^th. This month also saw the end of the little tern breeding season at Rye Harbour, with at least five young fledging, the best result for several years.

A good month for the Lime Kiln moth trap, particularly as regards migrants. Highlights were diamond-spot pearl on 9^th, and breckland plume and ni moth on the 2nd, while there were also several records of Jersey tiger and humming-bird hawk moth. Similarly butterfly records during August included migrants such as red admiral, painted lady and several clouded yellow. Other notable invertebrates during August included 13-spot ladybird (below) on Harbour Farm on the 27^th, the first reserve record for this rare migrant, saltmarsh horsefly on the new saltmarsh on the 5^th, great silver water beetle at Castle Water on the 30^th and several sightings of both brown-banded and moss carder bee throughout. Plants in flower during included autumn lady’s tresses, rock samphire and Babington’s orache.

Image: Gilles San Martin