Wednesday, July 29, 2015

European Nightjar

The European Nightjar Caprimulgus europaeus can be a tricky species to study. Often, the male Nightjar’s unique churring call is the only sign that these migrants have arrived in the UK for the summer, unless you are lucky enough to see one silhouetted against the moonlight. This is a species associated with myths and legends. In many European languages, the Nightjar is known as the ‘goatsucker,’ with the genus name Caprimulgus deriving from the Latin for ‘milker of goats’. It was believed that Nightjars fed from goats due to often being found in close proximity to livestock. In reality, this insectivorous species would have been searching for prey associated with domestic animals. Others believed the calls of the Nightjar were the sound of witches hiding in the bushes.

Monday, July 27, 2015

Red Fox

Red Fox in the Forest of Dean setting out on its nightly hunting. The Red Fox mates from January through March. The female will make one or more dens right after mating. The extra dens are used if the original den is disturbed. A little less than two months after mating, the female gives birth to a litter of between one and ten kits. The male brings the female food while she is caring for the kits. The kits start playing outside the den when they are about a month old. The mother begins feeding her kits regurgitated food, but eventually she will bring them live prey to "play" with and eat. Playing with live prey helps the young kits develop the skills they will need for hunting. The kits leave their mother when they are about seven months old.

Thursday, July 23, 2015

Large Blue

The Large Blue is widely distributed throughout Europe except for the extreme north and southern parts of Spain. The Large Blue became extinct in the UK in 1979, but has since been re-introduced, though it still remains a rarity. The best local site to me to see them is Daneway Banks managed by Gloucestershire Wildlife Trust.

Wednesday, July 22, 2015

Hawfinch

The Hawfinch is a shy species, and therefore difficult to observe and study. It spends most of the day on top of high branches, above all during breeding season. During the course of the hawfinch's life it can only be seen on the ground while looking for seeds or drinking water, always near trees. While drinking and eating it is fairly aggressive and dominant, towards both its same species or different ones, even bigger birds.

Tuesday, July 21, 2015

Mating Glow-worms

I've been spending a lot of nights recently on a Nightjar study in the Forest of Dean (photos to follow), which, due to the crepuscular nature of the Nightjar, often gives opportunities for other interesting wildlife sightings, such as these mating Glow-worms. The light from glow worms is cold, and is a form of bioluminescence. It is far more efficient than most light sources we are familiar with. It is caused when a molecule called luciferin is oxydised to produce oxyluciferin, with the enzyme luciferase acting as a catalyst in the reaction. Adult Lampyris noctiluca do not have the same control over the oxygen supply of many fireflies, which can switch their lights on and off in an instant, and take minutes to switch on or off. Larvae, however, have smaller light-emitting organs and can twinkle briefly. Male glow worms have the same ability, but it is rare to see them glow.

Sunday, July 12, 2015

Adder

The female adder usually reproduces once every two years, returning to the site of hibernation towards the end of August or early September to give birth. The adder is viviparous, giving birth to between 3 and 18 live young which are initially encased in a membrane. After giving birth the female must feed intensively in order to build up sufficient reserves for hibernation (3). The young adders do not feed until the following year, but live off the yolk sac and fat reserves that they are born with. The adder reaches sexual maturity at three to four years of age.

Harvest Mouse

The harvest mouse is the only British animal with a truly prehensile tail that can be used as a fifth limb. When wrapped around a stem it can act as a brake or anchor. This makes it very nimble travelling and feeding in stems of cereals and grasses. They have a remarkable ability to sense vibrations through the soles of their feet. Larger animals in the vicinity can be sensed by vibrations passing through the ground and up the plant on which the mouse is feeding.

Tuesday, July 07, 2015

Golden-ringed Dragonfly

The golden-ringed dragonfly is a very large dragonfly which is on the wing from May to September. It is a dragonfly of small, acidic streams in moorland and heathland and may be found away from its breeding sites. The female of this species is the UK's longest dragonfly because of her long ovipositor. Golden-ringed dragonflies are voracious predators, feeding on large insects such as damselflies, other dragonflies, wasps, beetles and bumblebees. They are fast, agile and powerful flyers.

Monday, July 06, 2015

Marbled White

The female Marbled White was freshly emerged, and was in the process of drying out her wings after eclosion. At this stage she is unable to fly. The keen male spotted her hanging upside down, and they were instantly in copulation. However, the process of manoeuvring her in to position made her lose her grip and they both fell to the ground. Her soft wings crumpled and folded, meaning she had to crawl to the nearest blade of grass as quickly as possible, or she would never have been able to fly. She managed to do this, carrying the attached male as she climbed, and as shown in the photo, her wings unfolded perfectly.

Sunday, July 05, 2015

Goshawk

A Goshawk chick, which has been lowered from its nest high in the canopy in order to be processed (ringed, measured, etc) as part of the work we do at http://glosraptors.co.uk/. Goshawks are still persecuted and their nests are frequently robbed.

Thursday, July 02, 2015

Common Blue

Common Blue butterflies, in the process of making the species even more common. The brightly coloured males are conspicuous but females are more secretive. The colour of the upperwings of females varies from almost completely brown in southern England to predominantly blue in western Ireland and Scotland, but the colour is variable within local populations with some striking examples. Unlike Adonis and Chalkhill Blues, the dark veins do not extend into white fringes of wing margins.

Red-eared Slider

The population of Red-eared Sliders in the UK is largely a result of the illegal release of unwanted pets, where they exploit an ecological niche, as yet, untouched by any other species. In the UK they are omnivores, occurring in lakes, watercourse and wetlands; seeking out sheltered, sunlit areas where they often bask for hours. Branches over water, rocks and structures such as bird nests provide preferred basking areas. Red-eared Sliders target invertebrates e.g. dragonflies and their larvae, also bird nests and young birds. Their impact on birds is partly due to basking Sliders pushing nests down into the water together with any eggs; and partly due to predation of young birds by pulling them under water and drowning.

Wednesday, July 01, 2015

Red Fox

A Red Fox photographed during the onset of dusk in the Forest of Dean.