Beluga in the Thames!

Contrary to my normal style, this blog post’s title is a little more self-explanatory than usual. This is so that when I’m scrolling through the archives in fifty years time I’ll be able to instantly recognise what this post will be about: something I’d never even considered possible.

If I was looking ahead to today from this point last week, I would probably be wondering how I’d managed to book a flight to Greenland or Svalbard at such short notice, and why it was a mild 17 degrees at such high latitudes. At the very least, I would be curious as to where I’d sourced my drugs from. I cannot believe that this morning I was enjoying a plate of chips in the warm sun at a table outside the Ship & Lobster on Mark Lane in Gravesend, Kent, while behind me a Beluga surfaced, just behind a barge with the words ‘Working for the Tidal Thames’ inscribed on its side.

The whale was first found by Dave Andrews on Tuesday, and I imagine he must have had the shock of his life when he spotted it. I certainly would have, with this record constituting one of the most southerly records of this species in the world. Belugas have a circumpolar distribution, with the nearest populations to the UK being over 2500km away. I was surprised to find out that this is the 19th sighting of Belugas in UK waters, although they have chiefly been seen in the Hebrides, Shetland and Orkney, with outlying locations being off Northumberland and Northern Ireland, both in 2015.

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The stretch of the Thames where we saw the Beluga

Belugas are interesting among whales as they can easily tolerate brackish and even freshwater. They are quite at home in estuaries and during summer often travel hundreds of kilometres up rivers in search of fish. In the remote polar regions they usually inhabit, this is fairly risk-free. The Thames is something else, however. As you can see from the above photo, residing in the Thames is not without its dangers. During the short while we were watching the sub-adult Beluga, about half-a-dozen vessels passed right over where the Beluga was seen just minutes before including a couple of massive ships.

Although, ship strikes are not the only danger this whale may have to face. There is also, of course, a higher concentration of plastic in the river than it will be used to. If it ingests too much it will die a slow and painful death. No doubt the overall relatively balmy climate will have an effect, although I’m not sure exactly how. But if Belugas weren’t affected by warm temperatures, then they wouldn’t be restricted to such icy climes.

It will be interesting to see how this Beluga’s slight wander will pan out. The best case scenario is that it will be seen swimming downstream and into the North Sea, where its instincts will kick in and it will swim back north to where it ought to be. To finish this blog post, here is a video of the couple of times I managed to record ‘Benny the Beluga’ coming up for air (email subscribers may have to click through to the blog to view the video):

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Coot-like coot-foot

Scientific names, often consisting of a mix of Greek and Latin, can sometimes be a little peculiar. For example, Phalaropus translates to coot-foot, and fulicarius to coot-like, to produce the scientific name for the Grey Phalarope. It isn’t really coot-like on outward appearance at all, only the feet as suggested in the generic name Phalaropus.

Phalaropes are waders, but are unusual among the group as they have partially webbed feet (like coots). This allows them not only to feed along the muddy margins of wetlands but also to lead a pelagic lifestyle, often congregating in large numbers offshore on their way to spend the winter in tropical oceans. The nearest they breed to the UK is in Iceland and the east coast of Greenland. Phalaropes are also unusual in their breeding behaviour. Their breeding plumage is an attractive rusty-red although uncommonly among birds, the females have the more beautiful attire. This is because they perform the courtship displays as well as defend the territory. In this role-reversal, the males incubate the nest and look after the young as they are developing.

Grey Phalaropes pass through UK waters twice a year on their migration, although mostly keeping out of sight of dedicated sea-watchers on coastal headlands. This all changes, however, when events like those earlier this week occur.

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I was lucky to see this male Grey Phalarope in breeding plumage on the Svalbard Archipelago in Arctic Norway a few years ago.

On Wednesday, Storm Ali struck the UK, powering its way from the west with wind speeds in excess of 100mph. Less than two days later, Storm Bronagh also blew in from the Atlantic. The combination of these two systems had notable effects on sea-going birds, particularly Grey Phalaropes. Over the past few days they’ve been turning up all over the UK, including double-figure counts at locations in the South-West. Of this large number, around 60 were found at inland locations, one of which being Bough Beech Reservoir in Kent. This is only a half hour drive away from me, so I couldn’t resist the opportunity to see my first British phalarope.

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The Grey Phalarope at Bough Beech Reservoir. It has been aged as a first-winter, meaning that it hatched this year somewhere in the Arctic.

Sadly, as with any vagrant bird, it is likely that at least some of these displaced phalaropes will be unable to make it back to where they’re supposed to go. Storm-driven birds often use up a lot of energy on their wayward journeys and cannot find enough food where they end up. Furthermore, birds like these phalaropes have usually never seen humans before in their remote, high-latitude nesting grounds. Therefore, they are frequently confiding and approachable, putting themselves at huge risk. Fingers crossed that this one gets back on track!

 

Species no. 3000!

Admittedly Stratiotes aloides, known vernacularly as Water-soldier, is not the most desired plant to have in an ecosystem. It is possible that it is native in East Anglia and Lincolnshire however in Sussex, where this species became number 3000 on my pan-species list, it is more likely to be introduced.

Yesterday I joined the Sussex Botanical Recording Society on a visit to Court Lodge Farm on the Pevensey Levels, which possesses a rich assemblage of aquatic plants in the many ditches. Some special species recorded included Potamogeton obtusifolius (Blunt-leaved Pondweed) and Petroselinum segetum (Corn Parsley), the latter growing on the banks of the ditches rather than within them as was the case with the pondweed.

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An example of one of the ditches where we were recording. The majority of the water plants you can see in the photo would  be Lemna trisulca (Ivy-leaved Duckweed), Elodea nuttallii (Nuttall’s Waterweed) and the aforementioned Potamogeton obtusifolius (Blunt-leaved Pondweed).

Although despite these Levels specialities being present, for the ditches it is hard to escape the colonisation of several non-native invasive plants. Fortunately we didn’t come across any ditches which were dominated by these unwanted waterweeds however both Azolla filiculoides (Water Fern) and Hydrocotyle ranunculoides (Floating Pennywort) were found along with the robust growth of Water-soldier.

Water-soldier can be quite problematic for native flora. Small populations can, if left undisturbed by boats or large numbers of waterfowl, develop into armies. These can completely annex stretches of canals or ditches, out-competing ‘friendlier’ water plants for resources. The following quote is from the Water-soldier’s species account in the recently published Flora of Sussex: “On Pevensey Levels it has spread considerably, and in 2010 was found to be completely covering a ditch for several hundred metres”.

Despite this, I find its biology quite interesting. In the autumn it will begin to stop photosynthesising, and gradually lose the gas in its leaves that keeps it afloat. It will sink to the bottom of the ditch or canal where the water is unlikely to freeze. In the spring the increased strength of the sun’s rays will penetrate deep enough to allow the sharp, serrated, sword-shaped leaves to photosynthesise again, producing oxygen which gives the rosettes their buoyancy.

I was not originally planning to write a blog post on the Water-soldier until I realised today while inputting yesterday’s finds into my list that it fits into the 3000th slot. I am quite relieved that I have managed to reach this milestone, as the target I set myself in a blog post I wrote when I reached 2000 was to record my 3000th species before my 15th birthday. As of today I’m 14 years, 11 months and 1 day old. So I reached my target, but only just. It is hard for me to imagine stopping pan-species listing, however with upcoming GCSEs and A Levels I imagine I might have to slow down a little. But to keep it ticking, I have decided to set myself another target: 4000 by the end of 2019. Wish me luck!

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Two plants surrounded by Frogbit (Hydrocharis morsus-ranae) resembling miniature water-lilies.

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The snow-white flower of Water-soldier. The flowers are not seen too often, with the main method of reproduction being vegetative: the lowest leaves of the plant have axillary buds which will detach when the leaves decay and can disperse long distances before resprouting. This species is what’s known as dioecious – this means that male and female flowers are found on different plants. For some reason, there are very few if any male plants in England, so all reproduction in this country is vegetative as described above.

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The four or five plants in the photo here represent about half of the largest population of them I saw, luckily it hasn’t reached the levels of dominance seen at other parts of the Levels.

Sussex Rarities – Hairstreaks & Clubtails

This morning, having heard some exciting news on the website of the Sussex branch of Butterfly Conservation, I found myself in Ditchling Common Country Park, scanning bracken after bracken with my binoculars. I was looking for a Black Hairstreak or two. The windy and overcast conditions were not conducive to my hopes of sightings along the lines of the day-count of 98 that was made earlier in the month!

These numbers are quite extraordinary considering the fact that this species was only confirmed to be found in Sussex just over a week ago. Following a few battered individuals found at the same site last year, a survey has been undertaken to determine the presence of this colony. Its appearance here is particularly notable as this site is far from the existing distribution of this species in the UK. It is thought to be confined to a band of clay soil in the Midlands, mainly Cambs, Northants and Oxon.

The closest Black Hairstreaks have previously come to Sussex is Surrey, where they were introduced in the middle of the 20th century. However, the habitat at the introduction site was destroyed and the species disappeared there. The species is not known for their long distance movements or dispersal at all, in fact patches of identical habitat to where they are found elsewhere on the same site often go uninhabited due to the reluctance of the butterfly to travel long distances. Therefore it is thought that this colony is also an introduction similar to the Surrey one, although despite it only being discovered very recently it is likely that the species first appeared in the 1990s – this is because the expanse of the population at Ditchling Common suggests that it has been expanding for quite a while. It’s so slow that the rate of expansion, even of a healthy population, is estimated to be only about a kilometre per decade!

Now, back to this morning. The foodplant of the Black Hairstreak is Blackthorn, and it was in abundance at the country park. This was especially true at a corridor that extends from the fish pond south-west to the Folders Lane East. This was where we focused our searching, which turned out eventually to be the right idea. At 10.30 the sunshine finally made a prolonged appearance and the wind died down slightly. This appeared to trigger the daily emergence of the hairstreaks to warm up on the bracken. The first one we found was perched at quite a gradient on one of the fronds, perfectly angled towards the sun. After a few minutes of sitting very still, it switched sides rather in the fashion of a sunbather aiming for an even tan. As it had not yet gained enough thermal energy it was being quite ‘co-operative’, allowing for great views. This sighting was repeated with up to three other Black Hairstreaks, a very satisfying way to see a new butterfly species for me: not a common occurrence!

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Although the sexes are hard to differentiate on physical appearance, it is likely that those we found were females. The males will emerge earlier, in order to have established a territory prior to the emergence of the females. They will fiercely defend their territory, which is usually centred around an oak known as the ‘master oak’, and approaching the end of the flight period this activity will render them quite battered and damaged. It is likely that this species is past its peak already this year. The species’ very short flight period is one reason why this colony may have remained undiscovered for such a long period of time. Years where the population is dramatically increased compared to previous and following years are also characteristic of this species. It is likely that this year is one of these ‘boom years’ which is what may have lead to this year being the one in which this colony was finally discovered. So if you haven’t yet had a chance to visit this true Sussex rarity, I would recommend that you do so sooner rather than later. Their short adult stage will be over before the end of June, and in future years there probably won’t be as many as there have been this year.

Black Hairstreaks are not the only entomological rarity I’ve had the good luck to see in Sussex this month. At the beginning of the month I took a walk along a small stretch of the River Rother, near Fittleworth in West Sussex. Having been advised about their presence there by Amy Robjohns and Olly Frampton, I was on the lookout for Common Clubtails, a species that isn’t actually as common in the UK as its name suggests. On the British Dragonfly Society website it is described as “extremely local”, only being found on a few rivers in Wales and southern and central England.

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However, its scarcity on a national basis was certainly not evident along this tranquil, luscious river in the mid-morning sun. Along only a few hundred metres of the river we managed to find at least 10 either hunting along the river or perched on bankside vegetation and overhanging willows. The vast majority were males which were patrolling their recently acquired territories while many females would be seeking protection in the nearby woodlands away from the water. They will soon return to mate and lay a new batch of eggs, which will complete their immature stages in the silty riverbed within 3-5 years.

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Orchid on the Hill

The Early Spider-orchids Ophrys sphegodes at Castle Hill NNR have one of the best views of the South Downs as well as Brighton to their south-west. On the northern edge of Woodingdean, a chalk grassland slope supports this nationally scarce species, which has only a scattered distribution along the South Coast from Dorset to Kent.

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This orchid is named after its appearance, with its flowers apparently resembling the abdomen of orb-weaver spiders. However, its flower shape has evolved so that it resembles bees, which come to try and mate with the flower, known as pseudo-copulation. This is also the case in the perhaps more appropriately named Bee Orchid for example. To complement the shape of the flower, these orchids also release the scent of female bees which further entices the male bees to unknowingly pollinate the plants.

However this technique may show to be detrimental towards the success of the species in the face of climate change. Despite the strength and accuracy of the scents wafted by the flower, they cannot compete with actual female bees. Therefore, the plants most likely to pollinate and reproduce successfully are those which blossom after the male bee has emerged although before the females. Although sadly warmer spring temperatures are pushing the phenology (life cycles) of these two species out of sync.

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It is also interesting to observe the variation in the exquisite patterns shown on different individual flowers, such as these:

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Travelling to find these orchids (a new plant for me) was a perfect break from revision. Despite their rarity, there are several reliable sites such as Durlston Country Park and Dancing Ledge in Dorset, Samphire Hoe in Kent and of course where I visited today, Castle Hill NNR in East Sussex. I would definitely recommend looking for them before they stop flowering in early June!

 

Mid-March Moth Madness

After a snowy delay, last weekend it seemed like spring had finally sprung and temperatures rose into double figures. Looking at the forecast for this weekend and into next week however, it looks like the wintry weather will return once again which is very odd for this time of year. I’m usually a fan of a bit of snow, but only at the appropriate times of year. So I decided to write this blog post to try and keep my spring feeling going for as long as possible, before the snow showers begin to move in from the east again.

Saturday night was the first time I have put my moth trap out this year. In previous years I have been a little more keen, with very little reward and sometimes even null counts at this early stage in spring, so I decided to hold it off until now. And with the Beast from the East only about a week gone, my hopes were not particularly high. Although I was in for a surprise.

Most of the time, I just leave my trap out for the whole night and check it in the morning. However, on the off-chance of something notable (or anything at all!) being in there, I decided to look down from my bedroom window just an hour or so after switching on the light. To my surprise I saw what seemed to be an Oak Beauty already within the trap, so I rushed down to check if there was much else about.

To my immense surprise, there were at least 20 moths flying around the trap and on the nearby house wall. Most were March Moths as well as several more Oak Beauties, along with a couple of Tortricodes alternella and a Common Quaker. Already we had recorded around twice as many moths as I usually get in an early-spring night!

I was more than keen to check the trap the following morning. Unsurprisingly, there were moths everywhere, with the final tally being 55! I would be happy with that in May or September, let alone the first half of March! I will run through a few of the stand out highlights:

Small Brindled Beauty

This was the rarest moth that I caught last night, and the second time I’ve caught this species, the previous occasion being early March last year. It is most common in southern England, becoming rarer further north although classified as ‘local’ – found in less than 300 sites nationally. The females of this species are one of many winter and spring species that are apterous – lacking wings. The females of many of these apterous species seem completely unlike most moths to me, although I’m yet to find one myself.

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Small Brindled Beauty

Dotted Border

This species is unique among the early spring moths as it is one of the few Geometrid moths out at this time of year. In my experience it is usually the Noctuids (such as the Clouded Drabs, Hebrew Characters and the Quaker species) that are the most commonly trapped, although the most abundant species caught during this night were the 18 Oak Beauties which is a slightly unusual Geometrid species. The Geometrids can be distinguished by the way they hold their wings; most Geometrids hold their wings out to the side whereas most Noctuids fold their wings over their abdomen.

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Dotted Border

This species can usually be identified by the row of dots running along the bottom of the wing which you can see in the photo above. However, it is a variable species throughout its distribution and there are forms which are very dark making the row of dots (the dotted border) very hard to see.

Clouded Drab

This species is quite common especially where its foodplant Oak is plentiful although, despite its name, it is can be really nicely patterned. It is another species that is really variable, with many colour forms. We caught three, one of them in particularly was particularly good-looking, with its pattern enhanced by the flash on my camera.

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Clouded Drab

Hopefully the upcoming cold snap will be the last of the winter, and spring will be allowed to continue unabated. I look forward to moth trapping further once it warms up again, hopefully we’ll continue with some good numbers!

Final Tally

  • Common Quaker 3
  • March Moth 9
  • Oak Beauty 18
  • Hebrew Character 4
  • Tortricodes alternella 2
  • Small Brindled Beauty 1
  • Dotted Border 5
  • Clouded Drab 3
  • Small Quaker 8
  • Chestnut 1
  • Brindled Pug 1

 

Eastbourne Strikes Twice

This morning, after struggling through incredibly thick mud, I reached a huddle of birders all looking at a small Robin-sized bird with a faint blue crescent on its breast feeding on the edge of a large reedbed. It was a male Bluethroat, a fantastic record for the time of year and for Sussex.

The bird was first seen last Sunday at West Rise Marsh in Eastbourne and identified from photos on Tuesday. Luckily it stayed around and has since allowed many Sussex and national birders to see it although it has been elusive. Unusually for me, it was not as elusive when I went to see it as I immediately had it in my binocular view after arriving. Much better than standing around for hours in the biting wind which some birders have had to do over the past week!

It appears to be a White-spotted Bluethroat, one of two subspecies of Bluethroat that have been recorded in the UK. It seems to be the less frequent subspecies, with the Red-spotted Bluethroat being the other that sometimes reaches our shores. Due to the difference in latitude of the two subspecies’ breeding ground, they typically arrive at different times of year. The White-spotted is most commonly found in late March and April whereas the Red-spotted is more likely to be found in May. Although White-spotted is the earlier arriver, it is more likely that this bird has been wintering in the UK, rather than having overshot its breeding grounds on its spring migration.

Occasions of Bluethroats wintering in the UK are occasionally recorded, for example last year a bird was found in February in Lincolnshire which remained until the end of March. Presumably it then attempted to migrate to where it thinks its breeding grounds are. It will be interesting to see if this Eastbourne bird stays much longer and whether it tries to set up a territory here or flies elsewhere to breed.

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Fantastically, this is not the first Sussex rarity that Eastbourne has had to offer this winter. Black Guillemots, although they breed on remote islands in the north of England, are even rarer in Sussex than Bluethroats, so for one to turn up in Eastbourne’s Sovereign Harbour was quite special. It has been present since late November, although I waited until the New Year before going along to see it. It’s a wonderfully confiding bird in a great setting!

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