Sunday 31 December 2017

Wildlife Review 2017

Mammals

The year's mammal highlight may have actually been in 2016. In January news of an Otter recorded on a trail camera at the Main Pond came to light but sadly no actual date was forthcoming. This is only the second record for the Warren, the first being an old record of a tideline corpse.


Resident species recorded on site not unexpectedly include Rabbit. They had a good early year but numbers dropped rapidly early autumn. Although Myxomatosis occurs annually a new strain of Viral Haemorrhagic disease is prevalent in Devon and may have been the main cause. Fox is also resident on site with at least two dens, their tracks are easily spotted on bare sand along the Dune Ridge. They can be seen at quieter times of the day and are often around the car park at dusk.


 Fox - Lee Collins

Weasel and Stoat are more secretive with only a couple of sightings of each this year, usually seen dashing across paths,  but sometimes bird alarm calls can give their presence away as they move through undergrowth.

There were no sightings of Badger, but signs were still seen occasionally but there were no Grey Squirrel or Water Vole records this year; both still occur just over the railway line.


With cetaceans there was a change in fortunes with more Harbour Porpoise sightings this year with up to four seen in January, September, October and December.  Bottle-nosed Dolphin are however becoming scarcer with a couple of small pods seen in May (including calves) and August. More unexpected was a sighting of a distant pod of 20 Common Dolphin in August. Remarkably at least seven more were seen at the end of December feeding close inshore. There have only been two previous records (1997 and 2015).


Common Dolphin - Alan Keatley

Both Grey and Common Seal were present in ones, or exceptionally twos, on and off during the year, both offshore and in the estuary.


Common Seal - Alan Keatley

Reptiles/Amphibians


In preparation for the Beach Management Scheme the introduced population of Sand Lizard (along with any Common Lizard found) were safely collected and translocated from the Dune Ridge to Warren Point, over a hundred were collected giving an indication of their population levels. No records of other species were received, but surveys were undertaken in the Buffer Zone around the site of the proposed new visitor centre.


There was less good news for amphibians. Common Toad are normally well recorded with toadlets often to be seen in large numbers around the ponds following emergence, care having to be taken to avoid standing on them in peak years, however for the third year in a row there was no such emergence. Common Frog, introduced a few years ago, were also scarce, possibly due to a dry winter and spring with low water levels. Palmate Newt are however still present  with one being fed to a Little Grebe chick on the Main Pond!


Common Frog - Alan Keatley

Butterflies/Moths

The first butterfly of the year was a Peacock on 7th January, but it wasn't until early March that others like Comma and Brimstone appeared, followed in April by the first Speckled Wood, Green-veined White, Small Copper and Orange-tip, the latter still in very low numbers but with a welcome increase.


 Brimstone - Alan Keatley

Overall it was a mixed year for butterflies on site with good numbers of Meadow Brown, including the first May and another November record, Gatekeeper, Large & Small White, Small Skipper, Small Copper, Brown Argus and Common Blue at varying times during the summer. However Large Skipper was notably scarce especially compared with its smaller cousin and Small Tortoiseshell is best now described as uncommon on site with only a handful of sightings this year.


Three other previous residents were recorded but only as occasional singles; Ringlet, Marbled White and Holly Blue, whilst Green Hairstreak was completely absent. However three sightings of Brimstone were encouraging for this less than annual species.

Most worryingly the nationally declining Wall Brown was not reported beyond the first generation; hopefully the realignment work will not prove the death knell for this species on site.

Amongst the migrant butterflies Red Admiral were seen moving through in good numbers throughout the autumn with smaller numbers of Small Tortoiseshell, Large and Small White. In contrast Painted Lady was only occasionally seen and Clouded Yellow was decidedly scarce with just a couple of sightings. A fritillary species briefly seen on a couple of occasions in early July was most likely a Dark Green, potentially only the 2nd record in 50 years. The butterfly year ended with a Red Admiral on 1st December.


Red Admiral - Alan Keatley

No moth trapping was carried out this year but day flying species included good numbers of Yellow Shell emerging on time in May and in late July hundreds of Six-spotted Burnet could be found in the Back Meadow and Greenland Lake along with a few Yellow Belle. Brown-tail nests were found in good numbers in remaining areas of bramble but other hairy caterpillar species were again scarce with only a few Jersey and just one Cream-spot Tiger noted. Cinnabar also continued to decline.


The usual migrant species; Silver Y, Rush Veneer and Rusty-dot Pearl were scarce but the rare migrant Crimson Speckled was found on Warren Point in October, the first for the Recording Area.


Crimson Speckled - Lee Collins

Dragonflies/Damselflies

There were low numbers of Blue-tailed and Azure Damselfly, but both remain the two commonest species on site. There were no reports of Small Red-eyed Damselfly for the third year running, this previous breeding species is now probably lost from site. There were also no reported sightings of Black-tailed Skimmer or Broad-bodied Chaser, both previous residents.


Other larger dragonflies fared better with Hairy Dragonfly still present but in very low numbers. The first Emperor emerged in June and several could regularly be seen patrolling the ponds and woodland edges. Numerous Migrant and Southern Hawker were evident in late summer and autumn and there were reasonable numbers of Common Darter late into the year with the last record on 23rd November.


Migrant Hawker - Alan Keatley

Migrants included record numbers of Golden-ringed Dragonfly whereas from further afield the Recording Area didn't miss out on the national influx of rare species with the site’s first two confirmed sightings of Vagrant Emperor (May & October) and two June records of Red-veined Darter. However these rare visitors do not compensate for another poor year, particularly for damselflies.


Red-veined Darter - Alan Keatley

Bees/Wasps
 

The Warren's varied flora remains vital to this important group of pollinators from the ubiquitous feral Honey Bee to the less common solitary bees.

It has been an eventful year with two new bumblebees for the Recording Area; the overdue Tree Bumblebee, a continental species on the increase and the less expected and declining Heath Bumblebee. The first Bumblebee’s of the year; Buff-tailed, Red-tailed and Common Carder appeared in March utilising Sallow, Gorse and the few remaining Daffodils as important early pollen sources.


Tree Bumblebee - Alan Keatley

In April solitary bees appeared on the wing with Buffish Mining Bee (Andrena nigroaenea) and Short-fringed Mining Bee (Andrena dorsata) predominant. In June more species were on the wing with dune specialists Sandpit Mining Bee (Andrena barbilabris),Silvery Leaf-cutter Bee (Megachile leachella) and Large Sharp-tailed Bee (Coellioxys conoidea) all noted.


Buffish Mining Bee - Debs Rylands

As summer progressed into July Black-thighed Epeolus (Epeolus variegatus), Little Flower Bee (Anthophora bimaculata) and the Pantaloon Bee (Dasypoda hirtipes) were seen with increasing numbers of Tree and Garden Bumblebee.

As the days shortened Ivy bee (Collates hederae) appeared on cue at the end of September but had virtually disappeared by the third week in October. However Common Carder Bumblebee were seen on warm days in October with Honey bee still on the wing well into November. Buff-tailed Bumblebee was still active until the end of the year on ornamental Hebe shrubs around the Boathouse.


Ivy Bee - Alan Keatley

Identifying many wasp species to species level can be challenging to say the least so it is not surprising that there were fewer recorded on site compared to bees. However the more readily identifiable species seen this year included a Bee Wolf (Philanthus triangulum) colony discovered in the Buffer Zone, with others seen along the Back Path, White-spotted Spider wasp (Episyron rufipes), Red-banded Sand wasp (Ammophila sabulosa) and Slender-bodied Digger wasp (Crabro cribrarius).

The predominant social wasp on site appears to be German wasp (Vespula germanica) which can often be seen gathering wood pulp from fencing for their nests.

Flies

A Devon Fly Group meeting on site in early August recorded the very rare and threatened cranefly, Geranomyia bezzii. It’s an intertidal species with larvae that live on mats of green Enteromorpha algae.  The species in known from just a handful of sites along the south coast from Hants to Devon so it was good to confirm it was still present on the Warren.


Geranomyia bezzii - Rob Waton

Apart from the cranefly, the best finds were two muscids; Helina deleta and Musca osiris, both species with very few previous records in the UK.  The latter is probably a migrant, and perhaps the former too. 

Other good dipteran finds included the muscid Coenosia karli, a nationally scarce species with just a couple of previous records from Devon; Villeneuvia aestuum, a nationally scarce muscid of saline situations; Muscidideicus praetextatus, a nationally scarce dolichopidid; the tachnid Platymya fimbriata, not nationally uncommon but a first for Devon; the pipunculid Tomosvaryella littoralis was another county first; and the coastal anthomyiid Anthomyia confusanea had only one previous record in Devon although it is a widespread species nationally.

Hoverflies recorded this year included the bumblebee mimics Cheilosia illustrata (Hogweed Cheilosia) and Volucella bombylans (Bumblebee Hoverfly). The hornet mimic Volucella zonaria (Hornet Hoverfly) and the territorial Volucella pellucens (Large Pied Hoverfly) were regularly seen in the wooded areas. In the more open areas were the drone flies Eristalis tenax (Stripe-eyed Dronefly), Eristalis nemorum (Stripe-faced Dronefly) and Eristalis pertinax (Tapered Dronefly) plus Helophilus pendulus (The Footballer), Syrphus ribesii (Common Banded Hoverfly) and Sphaerophoria scripta (Long Hoverfly).


Volucella pellucens - Alan Keatley

Migrant hoverflies recorded included the almost ubiquitous Episyrphus balteatus (Marmalade Hoverfly), Scaeva pyastri (Pied Hoverfly) and the Eupeodes corollae (Migrant Hoverfly).


Scaeva pyastri - Alan Keatley

More discoveries were found amongst the true flies with the first site record of the soldierfly Ornate Brigadier (Odontomyia ornata). Both Dune Robberfly (Philonicus albiceps) and Kite-tailed Robberfly (Machimus atricapillus) were noted hunting on the Dune Ridge and in the meadows respectively by June, whilst earlier in the year two Dark-edged Bee-fly (Bombylius major) were on the wing in early April, the first records for several years.



Dark-edged Bee-fly - Debs Rylands
Other Invertebrates

The Warren has an impressive list of grasshoppers making it one the most outstanding sites in the UK, however with exception of Lesser Cockroach none of the rarer species were noted this year. The regular species recorded included Common Groundhopper, Meadow Grasshopper, Long-winged Conehead and Great Green Bush-cricket.

Similarly beetle sightings are usually of the more obvious and colourful species with Black and yellow Longhorn (Rutpela maculata) and Thick-legged Flower beetle (Oedemera nobilis) regularly seen this year. The removal of Trre Lupin has lead to large reduction in Ladybird records. The previous aphid abundance no longer available to them. Apart from the large and colourful Wasp Spider (Argiope bruennichi) the only other spider species of note was the first Warren record of a Pirata piraticus, seen on the Main Pond in May.


Rutpela maculata - Alan Keatley

The Warren shared in the wildlife phenomenon of the year with unprecedented numbers of Portuguese Man O'War washed up on the beach. Tens could be found from Langstone Rock to Warren Point. There had been only one previous site record. Barrel Jellyfish again came ashore in large numbers early summer.

Portuguese Man O'War - James Marshall

Plants

Two new species were added to the Recording Area’s extensive list of plants this year, the second and third records for Devon respectively.  This first was the discovery of the nationally scarce Mossy Stonecrop (Crassula tillaea) in the Buffer Zone in June with Narrow-leaved Ragwort (Senecio inaequidens) found on Warren Point in October.  The latter is a non-native species frequent around docks and was perhaps accidentally introduced with the pipework used to pump sand for the beach recharge.

2017 was the Warren's best year for orchids with a welcome increase in numbers of Southern Marsh Orchid and a profusion of Marsh Helleborine and Autumn Lady's-tresses at varying times. A new colony of Pyramidal Orchid, including a rare white variety, was found on Warren Point, thanks to some temporary fencing the Bee Orchid colony increased from three to 16 spikes near the Dune Pond and a single Green-winged Orchid again flowered in Greenland Lake.

Bee Orchid - Alan Keatley

The Warren's star attraction, Sand Crocus, first appeared on 19th March and numbers continue to increase in Greenland Lake. With careful looking the tiny and rare Small Adder’s-tongue could be found in bare areas of Greenland Lake in early summer, the only mainland site in the county.

Small Adder’s-tongue - Alan Keatley

On the downside Devon’s only Belladonna Lily was lost to the reprofiling of the Dune Ridge. However this is an non-native species, the overnight loss of a large patch of twenty Sea Holly plants on Warren Point show how susceptible native dune flora is to autumn storms, changing weather patterns and associated erosion.
 
Thanks to Alan Keatley for all his help with the review and to all those who also submitted records and pictures to the Recording Group during the year.
 
 

1 comment:

  1. Thank you for this really interesting and informative review. Dawlish Warren reserve is a very special place.

    ReplyDelete