All text in Italics is taken from primary or on-line sources; citations given.
I returned to Cuckmere Haven on 10.09.21 because I wanted to see if I could find some Sea Aster Bees: I did. (I have verified my identification with expert entomologists and entered the observation on iRecord; currently awaiting verification)
Sea Aster Bees, Collete halophilus are on the IUCN International Union for Conservation of Nature Red List Kuhlmann, M.2013. Colletes halophilus. The IUCN Red List of Threatened Species 2013: e.T13306686A13309503. https://dx.doi.org/10.2305/IUCN.UK.2013-2.RLTS.T13306686A13309503.en. Colletes halophilus (iucnredlist.org)
From Colletes halophilus, a bee of saltmarshes. Aculeate Information Sheets. How the habitat requirements of BAP aculeates relate to their HAP. Produced by Hymettus Ltd - The UK Aculeate Conservation Group. Conservation Action for Ants, Bees and Wasps January 2009, Colletes Eng revised 2009.pdf (hymettus.org.uk) accessed 12.09.21:
General biology: Colletes halophilus is a mining bee which is associated uniquely with coastal saltmarshes and adjacent stabilised sandy dune areas, sea walls and low maritime cliffs.
The bee has a very restricted range globally, and its association with salt marshes makes it particularly vulnerable to climate change, the associated rise in sea level and the policy outcomes associated with coastal management and sea defence.
The bees are active in late summer and are on the wing in August and September. The female bees forage predominantly at the flowers of Sea-Aster (Aster tripolium). However, they will also visit flowers of other members of the plant family Asteraceae for nectaring, or when their preferred pollen source is unavailable.
The nest burrows are excavated in stabilised sandy material with sparse vegetation cover to ensure maximum ground surface temperatures. In ideal sites, the nests may be formed into large aggregations numbering many thousands of individual burrows.
Status in UK In UK, the bee is found along the North Sea and Channel coasts, from Spurn Point in the north, southwards through Lincolnshire, Norfolk, Suffolk, Essex, Kent, and then east through Sussex to Hampshire and the easternmost parts of Dorset. There is a single, anomalous, record from the Breckland heathlands.
The bee nests close to its forage plants in suitable exposed places. Occasionally, large nesting aggregations can be found but these are rare in UK The bee was not listed in the Red Data Book 1 (1987), but was accorded Nationally Notable (a) status in the subsequent Review 2 (1991).
The extreme localisation of the species, both nationally and globally, has resulted in it being included in the new BAP lists (2007) Reduction and degradation of salt marshes, strengthened existing coastal defences, expanding urban sprawl, continued development of brownfield sites, and inappropriate grazing regimes all place increasing pressure on this specialised bee species.
Carefully considered and controlled “managed retreat” may, conversely, provide opportunities for conservation. 1 Shirt, DB (ed) 1987 British Red Data Books: 2. Insects. Nature Conservancy Council. 2 Falk, SJ 1991. A Review of the Scarce & Threatened Bees, Wasps & Ants of Great Britain. Research & survey in nature conservation, No. 35 Nature Conservancy Council
The current distribution of Colletes halophilus in the UK Known from the south and east coasts of England, from Christchurch Harbour to Spurn Head. There is a single inland record from a sandy Breckland heath (Map prepared from BWARS dataset)
The Global distribution of Colletes halophilus Colletes halophilus is restricted to the Atlantic region of Europe, from the Friesian islands in the north to the south western Biscay coast of France. There are also important populations on the eastern and southern coasts of England (Map prepared from M. Kuhlmann dataset)
Key Points:
• The bee has an extremely restricted distribution globally
• The bee is liable to be vulnerable to rising sea levels
• Effective management requires conservation action to protect the 2 partial habitats needed for nesting and foraging
1. Stabilised exposures of sand or clay
2. Large stands of Sea-Aster
• The bee requires its key habitat components to be available on a landscape scale A mating ball of males of Colletes halophilus on sandy nesting substrate at Saeftinghe (NL).
There were four listings of Colletes halophilus In East Sussex on iRecord
The goal of iRecord is to help bring together wildlife sightings from many sources, so that they can be checked by experts and made available to support research and decision-making. It is operated by the Biological Records Centre (BRC) as part of the work of the UK Centre for Ecology & Hydrology (UKCEH).
iRecord is a website for sharing wildlife observations (biological records), including associated photos – you can register quickly and for free. Once registered, you can add your own records for others to see, and you can see what has been recorded by others. Your data will be kept secure and will be regularly backed up.
Automatic checks will be applied to your observations to help spot potential errors, and experts can review your sightings. All wildlife sightings are shared with other users and made available to National Recording Schemes (and their county recorders where relevant), and to Local Environmental Records Centres. Most records are also shared more widely via the NBN Atlas, and with a range of bona fide organisations for research and conservation. About iRecord | iRecord (brc.ac.uk)
Screen shots of distribution of Sea Aster Bees in East Sussex Explore all records | iRecord (brc.ac.uk) accessed 12.09.21
Here are some photos of Sea Aster, to demonstrate its extraordinary and restricted habitat - intertidal salt marsh. The sea aster's ability to survive in saltmarsh conditions sets it apart from its cousins, as this kind of endurance requires some impressive adaptations; being partially submerged in salt water for half the day is not easy! Sea aster - Inner Forth Landscape Initiative
The sea aster ... is a native that adds a splash of vibrant purple and yellow to our coasts.
Distribution
Sea aster can be found scattered across the coast of the UK, although it is much sparser in the north-east of Scotland.
Habitat
Often found in salt-marshes and estuaries and occasionally on cliffs. Sea aster is scattered throughout the British coast, although is absent from parts of north-east Scotland.
Best time to see
Flowers from July to October.
Did you know?
Sea Asters particularly are a valuable source of nectar for late butterflies like the Red Admiral. This fact may also explain a traditional name given in Dorset and Somerset: Summer's Farewell. Plantlife :: Sea aster
Sea Aster Bees pollinating Sea Aster
The Sea aster mining bee (Colletes halophilus) is a rare bee restricted to the margins of salt marshes in East Anglia and the Thames Estuary, with occasional populations along the south and east coasts. The UK supports nationally important populations, with the bee restricted globally to the North Sea coastline.
The bee is named after its preferred food source, Sea aster (Aster tripolium), which flowers at the same time as the bee’s August emergence when they collect pollen and nectar for their young. However, climate change and sea level rise are causing their saltmarsh habitats to be lost, with further impact on the bee from development pressure in their Thames Estuary populations. Sea Aster Mining Bee | Buglife projects
Sea Aster Bee - one
Sea Aster Bee - one - detail
Sea Aster Bee - two
Sea Aster Bee - two - detail
Other Pollinators on Sea Aster
Of the pollinators observed during the two hours of observation at Cuckmere Haven, by far the most common pollinator seen were hoverflies, particularly Eristalis tena - about 10 times as many Eristalis tena as Colletes halophilus were observed; the next most common pollinator scene was the bumblebee Bombus terrestris
Drone Fly Eristalis tenax
With brown-and-orange markings, the Drone-fly looks like a male Honeybee, but is harmless to us. This mimicry helps to protect it from predators while it searches for nectar in gardens and urban areas.
The Drone-fly is a very common, medium-sized hoverfly that is an excellent Honeybee mimic. It is one of several species of related hoverfly whose larvae are known as 'rat-tailed maggots' and live in muddy water, feeding on decaying organic matter. Adults feed on nectar in various habitats and can be seen throughout the year, emerging from hibernation to feed on Ivy flowers on milder winter days.
The Drone-fly is one of several related hoverflies that are Honeybee mimics. With a dark-brown body, orange patches on the sides and top, and a covering of orangey hair, it does a good job of looking like a Honeybee. Key differences include the lack of a stinger and 'waist', and only one pair of wings. Drone-fly | The Wildlife Trusts
Buff Tailed Bumblebee Bombus terrestris
One of the ‘Big 7’ widespread and abundant species, found in a wide range of habitats across the UK. Less abundant in Scotland than it is in England, but has been increasing in recent years. At least in cities in the southern UK the species is becoming winter-active, with nest establishment in October-November and workers flying all winter, feeding particularly on Mahonia bushes. A large species with dark yellow bands at the front of the thorax and middle of the abdomen, queens are the only caste which actually have buff-coloured tails: in workers and males the tails are white, although males in particular often have a narrow but distinct yellow-buff band at the front of the tail. Buff-tailed bumblebee - Bumblebee Conservation Trust
Buff Tailed Bumblebee Bombus terrestris - detail
Buff Tailed Bumblebee Bombus terrestris
Buff Tailed Bumblebee Bombus terrestris - detail
Buff Tailed Bumblebee Bombus terrestris - detail
Buff Tailed Bumblebee Bombus terrestris
Buff Tailed Bumblebee Bombus terrestris - detail
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