Chalk Stream BioBliz

On 11th May 2024, Bishop’s Sutton held a village BioBlitz. A group of around 40 experts and enthusiasts met at the Village Hall to explore the village, to  get a better idea of what wild living things live there and where they are  found. 

On the day, 177 observations were recorded, with a total of 147 species of  plants and animals. 

After the event the total list for the village stood at 164 species

For the full data and information on the findings go to the Project page at Inaturalist.org

The mammal count for Bishop’s Sutton stands at 16 species.

The Bat Walk in the evening of the BioBlitz was popular, with more than 20 people exploring the churchyard and riverside with James and Harriet from the Hampshire Bat Group. Using bat detectors to identify the echo-location calls of the different bat species, walkers identfied Common and Soprano (Pygmy) Pipistrelle, Noctule and Serotine bat. Later analysis of ultrasound recordings from Sutton Court Woodland identified the presence of the rare Barbastelle bat too.

The chalk stream bat, Daubenton’s, is known to frequent the Alre around Bighton Lane bridge, but failed to put in an appearance on the night! On the ground, rodents observed around the village include Wood Mouse, Field and Bank Vole, together with Water and Pygmy Shrew; of course, the Brown Rat is the rodent most often seen.

The elusive Water Vole, which we know from older records was once frequent from Water Lane to Bighton Lane, is believed to be present, but so far only its droppings and feeding remains have been seen.

These attract predators, including Weasel and Fox. The stream is also visited by the Otters which frequent the headwaters of the Itchen. The fields below the railway line often holds Brown Hare, which have been seen crossing the road at Bighton Lane Bridge.

Bishop’s Sutton awaits a comprehensive bird survey.

Recent records include Mallard, Gadwall and Little Grebe (Dabchick) on the wildlife ponds and stream; Grey Heron and Little Egret on the streams and cressbeds.

The Mute Swan pair that nest most years at Bighton Lane are a well-loved local presence, as are the Rooks that nest in the tall Beeches.

Cetti’s Warbler, a recent colonist from the South, can be heard singing from thick cover by the river. Originally a Mediterranean species, the first British record was at Titchwell in 1963; since then, this bird has colonised most of southern England. We think that milder winters driven by climate change mean that the small river flies that Cetti’s Warbler feeds on are more likely to survive the winter. Cetti’s is now the only British warbler that doesn’t migrate south for the winter.

Kingfishers can sometimes be seen, perched above the water or as an azure blue streak in flight.

As well as the ubiquitous Moorhen, the secretive Water Rail can occasionally be glimpsed in thick reedbeds and river margins.

Local owls include Tawny, Little Owl and the declining Barn Owl.

The clear waters of the chalk stream hold Three-Spined Stickleback and the Chabot Bullhead, which spends the day hiding under rocks on the river bed.

From analysis of otter spraint (droppings), we believe the Bullhead is the favourite food of the Otter locally, as it is for the Kingfisher.

The bridge at Bighton Lane is a popular observation point for Brown Trout. Some large specimens frequent the area, together with introduced Rainbow Trout.

48 species of insects and spiders have been recorded around the village.

The puddles that form along the permissive path towards Water Lane when groundwater is high in Spring are patrolled by Wolf Spiders.

The Bee Walk on the BioBlitz day found Garden Bumblebee, White-tailed/Buff-tailed Bumblebee and Common Carder Bee, together with Honey Bees.

Other pollinators include hoverflies such as the Broad-banded Aphid-eater.

One young visitor discovered a large colony of the Red Mason Bee in the garden of Bishop’s Court.

A Hornet was also observed – fortunately identified as the native European Hornet, not the invasive Asian Hornet which is a cause of concern for our native insects.

Grassland and woodland around the village was found to hold 5 species of butterfly on BioBlitz day, including Brimstone, Red Admiral, Orange Tip, Holly Blue and Small White.

A previous moth trapping night found Broad-bordered Yellow and Straw Underwings, and the Spongy Moth, as well as Vine’s Rustic, Rustic Pine Borer and Small Waved Umber, together with Common Carpet Moth and the Peacock Moth.

Beetles and bugs include the Black-headed Cardinal Beetle and the Sloe Bug. The Harlequin Ladybird, an Asian species introduced for biological control, is present and may compete with native Ladybirds.

In the Summer, the metallic blue of the Beautiful Demoiselle can be seen, although the area in general seems to lack Dragonflies and Damselflies.

The chalk stream holds a rich diversity of insect life, albeit with fewer species in the headwaters which occasionally dry out as a winterbourne. The Alre is a good site for predatory Diving Beetles, and large numbers of Caddis flies lay their eggs, with the larvae making their distinctive cases out of stones and vegetation. Mayflies such as the Large Dark Olive and the Blue-winged Olive are indicators of the health of the stream.

A botanical survey during the BioBlitz counted some 88 species of plant. 7 species of fungi have been reported.

The old brick façade of Bighton Lane bridge supports mosses, including Silky Wall Feather-Moss, Wall Screw[1]Moss and Grey-cushioned Grimmia.

The hedgerows and field margins feature trees such as Ash, Oak and Beech with Hazel, Holly, Elder and Field Maple, as well as Hawthorn and Blackthorn, with White Dead-Nettle, Ground Ivy and Woundwort in the hedge bottoms, giving way to abundant Cow Parsley in Summer.

The damp spring-fed grasslands feature grasses including Yorkshire Fog and Meadow Foxtail, as well as Meadow and Creeping Buttercup, Daisy and Sorrel, with Thistles and Dandelion. Three species of Orchid appear in the wet meadows in early Summer.

Woodland areas hold spring flowers such as Lesser Celandine, Primrose and Dog Violet.

River margins and wet areas support Alder and Willow, with Marsh Marigold and Yellow Flag in Spring, with Fool’s Cress and Water Speedwell growing with Water Mint at the water’s edge. In Summer, the stream bed is cloaked in the deep-green fronds of Water Crowfoot with its white-yellow flowers, with Starwort and Water Parsnip.

Introduced species such as Snowberry and Red Bistort can also be found, although the village is largely free of invasive non-native plant species.

There is much more to discover in the survey area and the Parish as a whole. As the seasons change, and more people get involved, we aim to expand the species list.

Observations can be recorded for all to see on the iNaturalist website.

Project Page link - https://www.inaturalist.org/projects/bishop-s-su5on-bioblitz-11th-may-2024

The iNaturalist App
Find iNaturalist here - https://uk.inaturalist.org/ or on your iPhone or Android App Store. The iNaturalist app helps with ID of unfamiliar animals and plants, as well as lots of background information. Every observation contributes to an online repository of data. It’s FREE, initial registration required.

Or send observations (what you saw, where it was and a photo) to: Attention2Place@gmail.com We’ll add new observations to the database