Hertfordshire's 10 rarest wildlife species
PUBLISHED: 11:35 03 July 2018 | UPDATED: 13:28 03 July 2018
Our county is home to some very rare wildlife. Herts and Middlesex Wildlife Trust’s Charlotte Hussey lists the top 10 rarities (1 being the rarest) and where, if you’re lucky, you could spot them
A rare, shy heron, bitterns spend almost all their time hidden away in large reedbeds, where they feed on eels and other fish. Bitterns have wonderfully camouflaged plumage, helping them to blend into the reeds. They can also stand motionless for long periods to avoid detection.
In Hertfordshire there are only a few places to see this elusive bird. Head to Herts and Middlesex Wildlife Trust’s Tring or Amwell nature reserves during the winter. At Amwell there is a dedicated ‘Bittern Pool’ viewpoint to give the best chance of spotting one. You will need to be patient!
2. Black-necked grebe
Grebes are diving waterbirds, feeding on small fish and aquatic invertebrates. The black-necked grebe is small – about the same size as a moorhen. A rare breeding bird, the trust’s Hilfield Park Reservoir supports the only breeding colony of black-necked grebes in the south of the country. While this locked site is only accessible to trust members, the trust runs events to see this bird and experience the other wildlife on the nature reserve.
Pasqueflowers are now very rare and Royston’s Church Hill next to our Fox Covert Nature Reserve is the largest population in the country and the only place to see them in the county. Flowering for only a few weeks in early spring, this flower is restricted to just a few chalk and limestone grasslands and found on only a handful of nature reserves.
Legend has it that pasqueflowers sprang up in places that had been soaked by the blood of Romans or Vikings, as they often appear on barrows and boundary banks. It’s more likely that these sites are favoured because they tend to be undisturbed chalk grassland.
4. Stripe-winged grasshopper
Stripe-winged grasshoppers are rare in Hertfordshire, currently known from only two sites. They have very specific habitat requirements – dry, sunny grassland and heathland. Panshanger Park, owned by Tarmac and managed in partnership with the trust, supports one of our Hertfordshire populations and is a great place to try and spot them in the summer months.
The unusual looking herb-Paris is now restricted to just a few ancient woodland sites. With its whorl of four egg-shaped leaves, herb-Paris is known as the ‘herb of equality’ because all of its parts are considered equal and harmonious.
It is a perennial plant of damp woodlands, mainly on chalky soils, and its crown of understated, green flowers can be found blooming among bluebells and primroses in May and June. Head to our Balls Wood Nature Reserve to see swathes of these flowers in spring.
6. Green-winged orchid
These pretty pink or purple orchids can be found in unimproved grassland sites – areas that haven’t been treated with fertiliser. There are very few in Hertfordshire but they can be seen at one of the finest surviving wetland meadows in our county, the trust’s Hunsdon Meads, in early May.
Look out for flowers clustered around a single spike with three lobes. The name is derived from a hood formed by the sepals above the flower which appear lined with green veins.
7. Small blue butterfly
The small blue is the smallest of all UK butterflies and is only found on a few Hertfordshire sites in little colonies, where its sole larval foodplant, kidney vetch, grows. It disappeared from the trust’s Aldbury Nowers reserve for a time but returned within two years of restoration work to the site. In 2016 small blue eggs were found on its food plant, proving that this rare insect is now breeding on the reserve.
8. Water violet
A pretty, delicate flower, the water violet is actually of the primrose family. The flowers can be found in ponds and ditches in the south and east of England in May and June.
You will see their pale pink flowers coming up through the water, feathery leaves around it. Take a trip to the Trust’s King’s Mead Nature Reserve where a project in 2004 restored the water violet from 220 plants to over 8,000 in 2009!
The barbastelle bat lives in woodlands and has specific habitat requirements – roosting in the crevices of ancient trees.
The barbastelle is currently a flagship species for the trust and much research is going into finding out more about this elusive bat. Records are being picked up, but there are very few maternity roosts in Hertfordshire.
10. Water vole
The population of water voles has declined 95 per cent in the past 60 years and it has the unfortunate label of UK’s fastest declining mammal. This steep decline is partly due to the loss of riverbank habitat, but is chiefly the result of mass predation by American mink introduced to this country in the 1920s.
The trust’s water vole project has made great gains in conserving the species locally, with the biggest success to date being a reintroduction of 160 water voles to its Thorley Wash Nature Reserve near Bishop’s Stortford. Visit the site for a chance to spot one of these shy animals for yourself.
To find out more about these rare species and Herts and Middlesex Wildlife Trust local nature reserves, go to hertswildlifetrust.org.uk