Biology – Page 46 – David Bradley

Starling Murmuration in the Fens

LIFE ON THE FEN EDGE – WITH SIR DAVID ATTENBRADLEY

EPISODE 1: I HEARD A MURMUR

from the BBC, the Bradley Broadcasting Corporation

Sunset is still a long way off. But, there’s a peace settling over the reed bed at the Broad Lane balancing pond in Cottenham. Nevertheless, it seems an unlikely place to spend the night. But, that’s exactly what several hundred local residents are planning to do. They’re just waiting for the sun to go down and in they’ll come to make their bed.

The time is drawing near, a few birds have come home to roost and are calling from the trees. Almost as soon as the sun dips below the horizon, the first of the overnighters arrive, winging their way in from the local fields and making a flap about who gets to sleep where. And, then the crowds begin to arrive, everyone jostling for pole position in the race to find the most comfortable and safest spot to bed down for the night.

The arrivals are, of course, starlings (Sturnus vulgaris), and this is murmuration time. We do not see quite the magnificent flocks of millions that appear over the African savannah nor even the multitude thatÂ murmurates along Brighton Pier. But, this is Cottenham on the edge of the Cambridgeshire Fens and we have to make do with a mere two or three thousand of these birds settling down each winter night. Wave after wave arrives to find a roosting place among the reeds.

And then, the stragglers, the less prompt late back from the fields. Thankfully, there’s always a snug bed among the reeds. And, there’s no panic about who gets the top or the bottom bunk. Every roost is the same and every roost is as safe as the next from night-hunting predators with a taste for our feathered friends. They just have to hope there are no pike in that balancing pond.

LIFE ON THE FEN EDGE – WITH SIR DAVID ATTENBRADLEY

EPISODE 1: I Heard a Murmur
EPISODE 2: Goldfinch Dynasty
EPISODE 3: Young People’s Beat Combo
EPISODE 4: The Cumulus Dynasty

Is this the end of insects?

Even through the scorcher of a summer we just had, nobody was scraping moths and flies from their windscreens and headlights were they? Nobody has done that for a few years now…I know several friends have been wondering why that is…are insects simply avoiding the roads? No, of course, not. What’s happening is that insects are dying out, unfortunately.

The New York Times has finally caught up

Mottled Umber – Erannis defoliaria

UPDATE: 25 Nov 2019 First noted appearance of the year of a Mottled Umber, just a day later than in 2018. Didn’t reach the trap, roosted on the conservatory wall, was photographed and released into the front garden. The females are wingless, so these are definitely males. There are two LBAMs on the trap too, but nothing present by morning aside from a caddisfly and some diptera. My detailed mothing records for 2019 are available here.

This was the first new species to the actinic trap (night of 24th November 2018) for almost two weeks, having had numerous blanks and/or just the occasional Turnip Moth and a Dark Chestnut or two.

This species is the geometer moth Mottled Umber (Erannis defoliaria). The “geometers” all have larvae (caterpillars) that appear to measure the earth (they’re called inchworms colloquially in the US, I believe). Geo meaning earth, meter meaningÂ to measure.Â More mothematics here.

How the dog brain works

A lot of people, usually people who don’t have dogs, talk about dog psychology and how dogs see humans, specifically their owners and handlers as being like the alphas in the dog’s pack and that’s why they (usually) do what we command them to do and always come to us for food, tummy rubs, and treats.

The simplest of observations shows that this is not true. Most dogs on seeing a human walking towards them will, if they’re well adjusted (dog and human) may approach with caution and interact. But, if it’s a strange dog, the response is almost always entirely different. Now, the scientific evidence is in, in the form of functional magnetic resonance imaging (fMRI). Brain scans of awake dogs presented with human and canine faces show adjacent but separate regions of the brain being activated in response.

The researchers explain how working dogs were presented with pictures of canine and human faces. The human faces varied in familiarity (familiar trainers and unfamiliar individuals) and emotion (negative, neutral, and positive). Dog faces were familiar (kennel mates) or unfamiliar.

They found that the human face area activated in the dogs’ brains maps to the part of our brains we call the fusiform area and the dog face area maps to the human superior temporal gyrus. Both regions are critical for human face processing system in our brains, suggesting a past evolutionary link to our common mammalian ancestor and perhaps deeper back in time to the precursors of mammals.

The research paper can be found here.

St Mary’s Golden Plover

Golden Plover (Pluvialis apricaria) at St Mary’s Island, Whitley Bay, Northumberland, turn of the high tide 15th November 2018.

St Mary’s Island, near Whitley Bay, is a great place to see a variety of bird species. Here are some of the species that you might see on a visit:

Common Eider (Somateria mollissima) – These large sea ducks are a common sight around St Mary’s Island. The males have striking black and white plumage with a lovely green patch on the back of their heads, while the females are speckled brown.

Eurasian Oystercatcher (Haematopus ostralegus) – These black and white wading birds are commonly seen along the shore, probing the sand and mud for their favourite food – bivalves such as mussels and cockles with their large orange bill.

Turnstone (Arenaria interpres) – These small, plump wading birds are easy to spot with their distinctive black and white plumage and mottled brown plumage. They get their name from their habit of turning over stones and pebbles to find food.

Ringed Plover (Charadrius hiaticula) – These small, sandy-coloured wading birds are often seen running along the shoreline, looking for insects and other small invertebrates. Look out for another similar species Little Ringed Plover (Charadrius dubius), distinguished by yellow ring around the eyes.

European Herring Gull (Larus argentatus) – These large, noisy gulls are a common sight around St Mary’s Island. They are opportunistic feeders and will eat a variety of food, including fish, insects, and even rubbish.

Great Black-backed Gull (Larus marinus) – These are the largest gulls in the world, and are often seen patrolling the coastline. They are powerful predators and will take a wide range of prey, including fish, seabirds, and even small mammals.

Common Tern (Sterna hirundo) – These graceful birds are summer visitors to the coast, arriving in April and leaving in September. They are often seen hovering over the water, looking for fish to dive down and catch.

Northern Fulmar (Fulmarus glacialis) – These grey and white seabirds resemble gulls but have a distinctive tube-like nostril on their beaks, they’re often referred to as tubenoses. They are often seen soaring along the cliffs and offshore islands, and are known for their ability to produce an oily substance which they spit at predators in defence. Their flight pattern is with stiff-winged flapping.

Common Guillemot (Uria aalge) – These black and white seabirds are part of the auk family and are often seen in large colonies on offshore islands. Also known as the Common Murre. They have a distinctive high-pitched call and can often be seen diving underwater to catch fish.

Kittiwake (Rissa tridactyla) – These small gulls are easily recognizable by their black-tipped wings and bright yellow beaks. They are also known for their loud and distinctive “kitti-wake” call. Like other gulls, they are opportunistic feeders and will eat a variety of food including fish, invertebrates, and scraps of human food. They are known as Black-legged Kittiwakes outside the UK.

We’ve also seen Cormorant, Red Shank, Grey Heron, Dunlin, Sandpiper, Avocet, and several other species on the island. There is less chance of seeing Puffin, Shag, Gannet, but you never know…

Typical owl – Long-eared Owl

TheÂ Long-eared OwlÂ (Asio otus) is a typical owl, which means it is a member of the Strigidae family. On a flying visit to RSPB Saltolme on Teesside (a dry and winter sunny trip this second trip there for us), we headed over to the known roosting sites of the birds on the reserve. The noticeboards had said they were not “showing”. However, a warden was watching a tree intently and so we followed suit, but nothing came to sight.

Heading up the path, the warden spotted one in a dense woody thicket, it was only just visible with binoculars at about 15 metres distance and certainly you couldn’t see it without optical aids. He directed our sight to it, but Mrs Sciencebase spotted a second to its right and even more fiercely obscured by branches and foliage. I got a record shot of the first zoomed to 600 mm, f/6.7, t 1/2000s, ISO 12800.

It was dusky by now and very little light in the thicket. We needed to get back on the road, so couldn’t wait the hour or two before they took flight to begin hunting and had to leave before any significant Starling murmurations, although we did see a wonderful sunset of the chemical works! More of those in the next blog post.

Photographed at RSPB Saltholme

Limnephilus decipiens, a northern caddisfly

We were out for a dog walk at RSPB Ouse Fen (VC29) on a bright, sunny day. There various birds around, including Marsh Harriers, Kestrels, Reed Buntings, Bearded Reedlings, a Green Sandpiper, Wigeon,Â Tufted Duck, and the first winter thrushes we’ve seen this season (flock of Fieldfare).

This fellow sitting on the gate sneck caught my eye too, Limnephilus decipiens, one of the many northern caddisflies.Â I only had my 150-600 mm zoom, so had to lean against the barbed wire about 3 m along from the gate to get the shot, hence the very short depth of field.

A woodland fit for a kinglet

The Goldcrest (Regulus regulus) is the UK’s joint smallest bird (alongside the Firecrest, R. ignicapillus. They’re both usually about 90 millimetres long and weighing approximately 9 grams.

Both species favour pine trees, but you see them in other wooded areas and occasionally in gardens. I say “you see them”. But, they’re so small and flighty that it is quite hard to spot them and even harder to get decent photographs of them in their natural habitat.

They dart about in the darkest recesses of the woods, apparent only through their high-pitched whistling tweets and occasional flash of gold. So, I was quite pleased to catch one Goldcrest in the sunlight in one of our nearby woodlands, Rampton Spinney, about eight kilometres north of Cambridge.

The sunlight meant I could have a short shutter speed with the intention of freezing movement without the ISO being too high and the pictures noisy. These three shots were taken with a Canon 6D, with a Sigma 150-600mm zoom lens at full stretch, f/5.6, ISO 2500 and a shutter speed of 1/1500 second.

Cloudy night of autumnal moths

We have recently had some clear, cold, and damp nights and some rainy nights recently. The scientific moth trap has been running, but with very few lepidoptera making an appearance. I have been observing one or two specimens only each morning. That said, four species new to me in a couple of weeks and all added to my butterflies and moths gallery. However, the evening of 25th October 2018 was cloudy and thus a little warmer and while I cannot say that the trap was heaving this morning, there had been a few interesting species in the dark and one or two more present by morning.

Green Brindled Crescent (Allophyes oxyacanthae)

Common Marbled Carpet (Dysstroma truncata), dark form

Common Marbled Carpet (Dysstroma truncata), light form

There were two very different colourations of Common Marbled Carpet (Dysstroma truncata), Green Brindled Crescent (Allophyes oxyacanthae), two differently sized White Point (Mythimna albipuncta), and a rather interesting autumnal flyer, a male Feathered Thorn (Colotois pennaria). Also, not pictured, November agg (Epirrita dilutata), not seen any of the underwings recently, but there was a Lesser Yellow Underwing (Noctua comes), and finally, a Turnip (Agrotis segetum).

In that bottom photo of the Feathered Thorn I had to clone out all the yellow and white dog hairs that were on the carpet to allow the moth to stand out in the photo!

What’s the UK’s most common breeding bird?

It’s a classic pub quiz question: “What’s the UK’s most common breeding bird?”. Many people might think of Woodpigeon or House Sparrow, Starling, perhaps, because we see so many in our gardens. Indeed, House Sparrow is the most common bird in our gardens, but that doesn’t take into account the millions of birds in the countryside (ignoring chickens which aren’t wild birds). The answer to the question is in fact the Wren (Troglodytes troglodytes). There are about 8,600,000 breeding pairs of Wren in the UK compared with just 5,300,000 pairs of House Sparrow.

Bizarrely, when I posted this fact on Facebook with the above photo of a Wren at RSPB Titchwell, one friend asked, quite innocently, which is the most abundant UK breeding bird by weight? I assumed he meant mass and so I looked up the numbers and the average mass of a few species and did some calculations, I may well have overlooked a bird that comes in heavier, but here’s my Top Ten UK breeding birds not by number but by national tonnage:

Woodpigeon 457 g – 5.4 million pairs –> 4940 tonnes
Blackbird 100 g – 7m pairs –> 1400 tonnes
Collared Dove 181 g – 990,000 pairs –> 360 tonnes
Greylag Goose 3.6 kg – 46000 pairs –> 331 tonnes
Starling 75 g – 1.8 million pairs –> 270 tonnes
House Sparrow 32 g – 5.3m pairs –> 169 tonnes
Wren 9 g – 8.6 million pairs –> 160 tonnes
Chaffinch 25 g – 6.2m pairs –> 155 tonnes
Mute Swan 10 kg – 6400 pairs –> 128 tonnes
Robin 19 g – 6.7 million pairs –> 127 tonnes

Just outside the top ten, we have:
Song Thrush 80 g – 1.2 million pairs –> 96 tonnes
Dunnock 20 g – 2.3 million pairs –> 46 tonnes
Blue Tit 11 g – 3.6 million pairs –> 39.6 tonnes