Wildlife Review 2020: Butterflies & Moths

Butterflies

All of the regular Spring butterflies were seen, such as Comma, Green-veined White, Holly Blue and Orange-tip, the latter having a better year at least.

Small Tortoiseshell - Alan Keatley

There were a trickle of Wall Brown sightings between May and September, as the species retains a tenuous hold to the Warren. Scarce on site, the only Brimstone was seen on 8 August. Small Tortoiseshell had its best year in a long time with several sightings from 25 June. Brown Argus were difficult to find during hot spells of weather and were only seen in ones or twos. Rarely seen on site, on 31 July there was a record of a Silver-washed Fritillary.

Brimstone - Alan Keatley

Other species like Meadow Brown, Common Blue and Small Copper were recorded regularly in usual numbers and Gatekeeper were very numerous. Both Small and Large Skipper were down and only a few Marbled White and Ringlet were seen. However several Peacock caterpillar nests were found indicating a good breeding year and emphasising the importance of Nettle as a food plant.

The standout sighting of the year though was the second site record of the rare migrant Long-tailed Blue on 9 August. This mirrors other sightings along the English Channel coast at the same time. 

Amongst other migrants Painted Lady were notably scarce with only four well spread sightings, in contrast it was an exceptional year for Clouded Yellow with multiple sightings from June onwards. Double figures were seen on several days, and sightings continued into October. 

Clouded Yellow - Alan Keatley

Red Admiral had a long season passing through in steady, but not substantial numbers until November, however both Small and Large White moved through in good numbers this year.

Dawlish Warren Butterflies

Moths

No light trapping took place this year but just over 100 species were still recorded, with eight species added to the Warren list. Remarkably amongst these was the first record of the Nationally Scarce Red-tipped Clearwing, with one found nectaring on Water Mint on 1 August. 

Red-tipped Clearwing - Alan Keatley

More expected newcomers included Fox Moth, Orange-spot Piercer Pammene aurana, Oak Carl Tischeria ekebladella, Gorse Midget Phyllonorycter ulicicolella and Mottled Umber, bringing the Dawlish Warren Recording Area total to 672 species.

Mottled Umber

The day flying migrant Silver Y started to appear from mid May, with steady numbers through to October; a large influx on 13 June was alongside exceptional numbers of migrant hoverflies. Smaller numbers of Rusty-dot Pearl and Rush Veneer were noted with a Vestal on 16 September.

Dawlish Warren Moths

Devon Moth Group article

Friday 25th December (Christmas Day)

sunrise on Christmas Day - Ivan Lakin

For those whose festive break plans to see family and friends were scuppered by movement restrictions in response to the ongoing COVID-19 pandemic, there was some consolation in the form of a glorious morning that broke with bright tangerine skies that drew many onlookers with phone cameras to the seawall and welcome in the new day. Calm, crisp and clear; the sea was flat and floating about on it were 47 Great Crested Grebe (with another in the estuary); three Red-throated Diver, three Razorbill, the same imm Great Northern Diver and a Gannet.  With minus temperatures overnight across much of the country, some waterbirds were on the move with >100 Dunlin in off, seven Pintail (plus a pair in the estuary corner), some Dark-bellied Brent Goose, seven Wigeon, three Teal and a Shoveler all in off during the first hour of daylight.

Perched on seawall was the colour-ringed '632' Scandinavian Rock Pipit and another two un-ringed birds foraged in The Bight; only one petrosus Rock Pipit was seen today. 

Main Pond saw the return of five Shoveler; also two ♂ Mallard and a few Water Rail and Moorhen.  The Siberian Chiffchaff and a Firecrest were along Butterfly Ride/ Dead Dolphin Wood, and also in the woods was a high count of nine Great Tit plus single-figures of other tits, four colybita Chiffchaff, four Goldcrest, three Chaffinch, two Great Spotted Woodpecker, a Sparrowhawk and a Bullfinch.

Most of yesterday's Greenfinch were absent but 45+ Goldfinch were still present and mobile with at least four Siskin with them.  Two Raven and two Rook cruised overhead.

The tide took its time to rise and despite recent rains, observed height was for the most part less than predicted due to the dominant anticyclone (centre is 1042 mb).   Some 315 Dark-bellied Brent Goose were off Starcross but only 18 or so were within the site boundary today; another 152 Teal, another 13 Wigeon, six Red-breasted Merganser and the female Scaup was again present in the estuary corner.  On the rising tide were 103 Turnstone, 43 Redshank, seven Sanderling, five Greenshank and larger numbers of regular waders.  A Curlew with blue, yellow and black colour-rings was a locally ringed individual.  Among the gulls were c.320 Black-headed Gull, 25 Common Gull, six Great Black-backed Gull and an adult Mediterranean Gull. 

Wildlife news: distinctly smaller individuals (juveniles?) in a pod of 11 Bottlenose Dolphin leapt acrobatically clean out of the water at times and frenzied breaching as a tight group, back and forth across the bay this morning, seemed to involve hunting fish and social interaction. 

Merry Christmas to all.

not exactly a snow-covered shovel-handle, but it is an obligatory Robin

Thursday 24th December

A brief sleety shower made this the 18th consecutive day with precipitation and the the wintry feel was curtesy of a stiff north-northwesterly. This limited interest offshore to a dozen Great Crested Grebe, two Red-throated Diver, and the regular Great Northern Diver and drake Eider close offshore from Warren Point.  A pair of Shoveler returned to Main Pond; there, on Entrance Pond and on flooded areas were single-figures of Moorhen, Water Rail, two Mallard and two Common Snipe.  Around their margins were most of the six Meadow Pipit and four Pied Wagtail.

Woodland and scrub hosted 13 Long-tailed Tit, c.10 Blue Tit, five Great Tit, five Goldcrest, two Coal Tit, three Chaffinch, three Chiffchaff, two Bullfinch, two Song Thrush (one a singing ♂); one of the Firecrest and a ♂ Great Spotted Woodpecker.  Some of these birds and some of the mobile finches, which included increases of up to 45 Greenfinch and c.50 Goldfinch on site, made use of the bird feeders.  In more open areas were six Stonechat, six Cirl Bunting, five Skylark (on Warren Point, as usual) and a ♂ Kestrel.  Also seen, a Peregrine with prey flew toward Exmouth.

High spring tides are not always the best time to count all varieties of waterbirds here and instead neap tides and mid tides ranges can be a good time to attain representative counts of wildfowl before they melt into the saltmarsh to hide, or before they depart to roost or forage elsewhere.  Counts late morning included 169 Black-headed Gull (including those that departed south at dawn); 126 Turnstone (a December record); 159 Shelduck (a new site record count - see 13th December post), 76+ Dark-bellied Brent Goose, 51 Teal, 51 Common Gull, 34 Curlew, 22 Cormorant, 19 Redshank, 11 Shag (including a few seen offshore), eight Red-breasted Merganser, seven Wigeon, six Greenshank, another seven Great Crested Grebe, an adult Mediterranean Gull; the other Little Grebe that has befriended the resident Slavonian Grebe; the ♀ Scaup again on the near estuary shoreline; a Mute Swan and a Little Egret.  Another ten were in close attendance around the hooves of grazing cattle in Eastdon Fields, but they weren't Cattle Egret.   

The December record count of 126 Turnstone today was 'completely out of the park' with the previous record of 95 set back in 1987.  Initially, this might suggest a lack of attention given to this species but there have been 325 December count since 1980, and instead the answer is a little more interesting. Turnstone is unique in its habits on this estuary compared to other waders in that the majority roost at high tide along the Starcross breakwater, located only 1,100 metres north beyond Dawlish Warren's northern recording area boundary.  Three-figure counts are regular there from early-autumn to early-spring; by contrast, just a stone's throw away, over the past four decades there have been only about 24 counts of >100 Turnstone at Dawlish Warren.  However, another five such counts have occurred during 2020 alone - so what's changed?  The pattern of records here show that huge counts occur erratically, implying opportunism. Evidence of eutrophication (perhaps agricultural run-off or sewerage overflow) has been prevalent on the estuary since the summer with large piles of green algae piling up along the shoreline during certain states of tide and wind direction; Turnstone seem to like it and instead of pebble flipping elsewhere, a large proportion of the estuary's Turnstone descended along Dawlish Warren's neap tide waterline today, during what was a fresh northerly, and on the day after heavy rains brought lots of organic material down the river to mix up with still lots of algae.  Together, these conspiring factors created, it seems, the perfect set of conditions to attract Turnstone to the site today.    

Scaup - Alan Keatley

Wednesday 23rd December

In unsettled conditions, a first-winter Glaucous Gull appeared in the estuary corner just after 09:00 where it was mobile and only remained for about 15 minutes before it flew WSW over the railway and disappeared inland. It was, surprisingly, successfully twitched, which served as a reminder that running for a bird can make all the difference between dipping and scoring.  The female Scaup was also still present along the golf course shoreline so remains difficult to see from publicly accessible viewpoints.  

Tuesday 22nd December

Of the few casual waterbirds counts made, 143 Dark-bellied Brent Goose, 20 Wigeon and 18 Teal were likely to be genuine reflection of diminishing numbers in those species since, as is their established pattern, the majority of the estuary's populations move up the estuary at this time of the winter to flooded grazing meadows.  Also noted, two Mute Swan flew in from the south; two Little Egret, the Slavonian Grebe and the ♀ Scaup again. Offshore, some of the 19 Great Crested Grebe, two Razorbill and Red-throated Diver.  Two Collared Dove that crossed over the railway line into the site boundary airspace from the village were first to do so since 10th October.   

Sunday 20th December

Apart from the incessant pervasive cacophony of yapping dogs all day, it was lovely out with a lighter than predicted westerly, prolonged sunshine and temperature that rose to just shy of 11°C. The conveniently timed and moderately high morning tide additionally leant to the favourable conditions for waterbird counts in the estuary and a full set (except Herring Gull) was achieved. The run down was - 1,592 Dunlin, 760 Oystercatcher with another 57 in Eastdon Fields; 188 Dark-bellied Brent Goose, 172 Knot, 169 Grey Plover, 124 Shelduck, 100 Bar-tailed Godwit, 47 Common Gull, 48 Teal, 42 Common Snipe plus a Jack Snipe in the saltmarsh; 39+ Turnstone, 38 Redshank, 35 Ringed Plover, 31 Cormorant, 29 Black-headed Gull, 20 Curlew, half of which dropped in from foraging on Eastdon Fields; just 15 Wigeon, 12 Great Black-backed Gull, ten Sanderling, eight Red-breasted Merganser, six Canada Goose, four Shag, four Great Crested Grebe, three Greenshank, three Little Egret, two Grey Heron, a Kingfisher and the Slavonian Grebe joined up with a Little Grebe.

The highlight was yesterday's ♀/imm Scaup, which was again present in the estuary corner and moved further out so may be possible to see, at times, from publicly accessible viewpoints. 

A perplexing large larid stood on Finger Point was momentarily thought to be a 4 or 5 cy Yellow-legged Gull but on closer inspection was considered to be a hybrid of sorts, perhaps Herring Gull x Lesser Black-backed Gull.

Close offshore, another ten Great Crested Grebe, a few Gannet, the Great Northern Diver again close off Warren Point with the ♂ Eider, and a Red-throated Diver.

The Siberian Chiffchaff was calling in Entrance Bushes and likely the same bird seen near the hide, exactly 1 km NNE away, where twice seen before so this bird does range.  In addition, six regular type Chiffchaff, and also in the trees and scrub were ten Long-tailed Tit, eight Blue Tit, four Great Tit, three Goldcrest, two Bullfinch, a Coal Tit, a Chaffinch and a Great Spotted Woodpecker. A flock of nine Cirl Bunting took advantage of an abandoned tee on part of the golf course not in play today due to flooding. Other notables were six Stonechat and two each of Scandinavian Rock Pipit (un-ringed) and petrosus Rock Pipit and a Water Pipit at an inaccessible location; a Sparrowhawk, a Song Thrush and a Rook overhead. 

Wildlife news: a Common Seal swam almost up as far as Eales Dock, flushing some duck; and a Buff-tailed Bumblebee was disappointed to land on a blue flag that wasn't a flower, though many plants do still remain in bloom.

Saturday 19th December

A busy and colourful synoptic chart with a large deep depression (973 mb) that sat over northeast Atlantic looked rather ominous, but after 08:30 the site managed to dodge the worst showers and birding was quite productive.  A ♀ Scaup was the first of the year as it sheltered in the estuary corner.  Apart from one off Maer Rocks, Exmouth last November, this is the first to be seen from the site since 26th Nov 2016.  The site year-list is now on 184.

The morning spring tide brought in 1,070 Dunlin, c.845 Oystercatcher, suggesting a couple of hundred birds were missing; a hundred of these were reported today at their minor satellite roost north of Exton, others were inland on Eastdon Fields, presumably also around Starcross and a small flock flew in from west over Dawlish Warren village. Also 182 Dark-bellied Brent Goose plus nine Pale-bellied Brent Goose; 145 Bar-tailed Godwit, 128 Grey Plover, 108 Shelduck, 62 Great Black-backed Gull, 40+ Turnstone, including the usual seven below Langstone Rock when the tide dropped; 38 Sanderling, 38 Common Gull, 29 Redshank probed around puddles on the 14th fairway; 22 Cormorant, 20+ Black-headed Gull, 18+ Ringed Plover, ten Red-breasted Merganser, just three Curlew, a Greenshank, an adult Mediterranean Gull, a Kingfisher and the lonesome Slavonian Grebe.

Main Pond had seven Mallard plus the domestic thing; only one Shoveler (♂), a Little Grebe and single-figures of Water Rail and Moorhen.

After all of the recent rain, wellies are now required to bird some wooded areas.  There were sightings there of 14 Long-tailed Tit, four Goldcrest, two Chiffchaff, single Song Thrush, Coal Tit,  ♂ Great Spotted Woodpecker and ♂ Green Woodpecker. Around Greenland Lake roamed a flock of 66 Goldfinch with six Greenfinch, two Stonechat and from flooded meadows rose a dozen Meadow Pipit.  Also today, single Buzzard, Kestrel and a Sparrowhawk had a go at the woodpecker and the murmuration of 420 Starling over Main Pond at dusk.

Too choppy to see much on the sea, a light passage of Gannet and Kittiwake passed through south, also two Great Northern Diver and a Common Scoter.   On the tideline amongst the debris foraged both Norwegeian colour-ringed Scandinavian Rock Pipit '632' and 'AVP' and four petrosus Rock Pipit.

Thursday 17th December

Headlines: For the first time in well over half a century, public access to the bird hide area and to the entire length of the dune ridge path beside The Bight, is closed.  Teignbridge District Council (TDC) tweeted this news today having taken the decision to fence this off due to storm damage and sea erosion.  

Access to Warren Point remains possible along the beach with the first access point via a cutting in the dune ridge at groyne 15. Access is also available further along toward the end of Warren Point. Please note the beach has also washed away so when tides are ≥3.7 metres, Warren Point will be cut off. If you are there and that happens - just wait.

The Bight and estuary can still be viewed, more distantly than before, from various places around Warren Point. The positioning and length into the water of spur fences either side of Finger Point and 'recharge area' indicate when birds are likely to be roosting there, so please do not climb over them and read the signs.

There are just a handful of people whom have permitted access to the hide area via another route. If you see them there, really sorry, they'd like you to join them but that unfortunately is not possible in the foreseeable future.

It was self-evident and predictable this problem was going to happen, but no solution has been given, with TDC, Environment Agency and Natural England seemingly unable to agree on a way forward.

acknowledgement to Google Maps for the basemap; illustrations and captions - Ivan Lakin

As a result of limited access, the only waterbird counts managed were of some of the more obvious species at distance, 115 Shelduck, 17 Great Black-backed Gull, five Red-breasted Merganser, four Little Egret, two Mute Swan and the drake Eider.

From the seawall, the first Black-necked Grebe for the year, with some of the seven Great Crested Grebe. Also 13 Gannet, single Red-throated Diver and Guillemot.

Main Pond had three Shoveler (2 imm ♂, adult ♂), Water Rail, Moorhen and a Little Grebe. A greyish silent 'phylosc' was presumably the Siberian Chiffchaff in Dead Dolphin Wood, and also in wooded areas seven Long-tailed Tit, four regular colybita Chiffchaff, three Bullfinch, two Goldcrest, and single Great Spotted Woodpecker, Coal Tit and Chaffinch. In more open areas with scattered bushes, three Meadow Pipit, two Stonechat, four Cirl Bunting and a few mixed finches. At least 60 House Sparrow departed their roost, which has moved located to bushes beside the service road of the shops.

Monday 14th December

 The only notable report was of the Siberian Chiffchaff again, calling at the site entrance.

Sunday 13th December

A completely different day to yesterday's weather with a lively Force 5-6 southerly, milder (12°C) and dank with nearly constant mizzle or heavier bursts of rain all day. A 1½ hour seawatch from first light was productive with 163 Gannet, 50 Kittiwake, 20 auk spp. (mostly Razorbill); five Red-throated Diver, two Common Scoter, a Great Northern Diver, a fw Mediterranean Gull and the highlight a Great Skua through at 08:26. A few waders also passed, c.45 Oystercatcher, likely on their way to the Teign Estuary and other exposed shorelines to forage on the dropping tide; 8 Curlew (destination unknown) and a Turnstone; everything flew SSW. A Kingfisher briefly perched on riprap below the lifeguard hut. 

A mixed feeding flock that moved through Entrance Bushes contained presumed long-stayers - the two Firecrest and the Siberian Chiffchaff. Also in sheltered parts of the woods, four Goldcrest, four Bullfinch, a Coal Tit and a Great Spotted Woodpecker. As expected, single-figures of Shoveler, Mallard, Moorhen and Water Wail and a single Little Grebe were on Main Pond or Entrance Pond.

WeBS sector counts were timed to cover the 17:23 tide (Exmouth Docks gauge), was more than a third of a metre higher than predicted (4.16 metres) and lapped  the foot of already undermined and degraded sea defences. The combination of windy conditions, disturbance and high spring tide at dusk saw some waterbirds seek refuge in The Bight and this is where most of the impressive counts of 365 Dark-bellied Brent Goose and 64 Great Black-backed Gull were; and also the second highest ever count here of 128 Shelduck. 

This species continues to increase here and that long-term trend seems to be influenced by shifts in the estuary's population. The first chart below plots average (not maximum) WeBS counts per decade for each month for the entire estuary. Visually, this suggests little change in numbers during the early part of the wintering season (Oct - Dec) but in the latter part of the winter season (Feb - Mar), since the 1960s to the present, population declines on the estuary become more pronounced *.  

However, the picture is different at Dawlish Warren; its wintering population has generally increased or remained stable in every month (Oct - Mar) through the decades, but curiously as the winter progresses, two related but contrasting patterns emerge and this is shown in the second chart - one shows that Dawlish Warren holds a decreasing proportion of the estuary's Shelduck through the winter but over the decades since the 1980s (no data for 1960s and 1970s), proportions have become less small. Reasons for this are not yet known; what seems to emerge from this short analysis is that there are two interrelated factors benefitting Dawlish Warren's mid-winter population - in December, which despite it not being the peak count period for the estuary, it is the month when Dawlish Warren consistently supports the highest proportions of that estuary population (half of them in 2000s!); and whilst Jan - Mar is the peak count period for the whole estuary, despite long-term declines in those months, the proportions of those birds supported by Dawlish Warren has actually steadily increased in each comparative month over the decades. 

Population dynamics can be complicated but if by interpreting patterns that infers something about what the factors influence bird populations, then authorities can think about how best to direct resources for conservation outcomes on this internationally importance site.  

All this begins with raw data and that's down to the WeBS volunteers who braved the wind and rain today and on all previous count days, some of whom have done so for decades - we thank you.

* Note: that WeBS counts, or Birds of Estuaries Enquiry (BoEE) as it was known back in the 1960s and 1970s, did not conduct counts Apr to Aug so those are data gaps in the first chart below, not zeros; and sector data for Dawlish Warren is unavailable for those decades, hence missing from the second chart.

Data capture, analysis and presentation - Ivan Lakin

Off site, 33 Cattle Egret were again in fields on Easter Hill, north of Cockwood Marsh in the afternoon.