October Highlights

The autumn bird migration is now in full swing. This month will bring a mass arrival of thrushes including migrant Blackbirds, Redwings, Fieldfares and Song Thrushes. It is a good idea to keep those feeders topped up during this month as this can attract the common migrants such as Brambling, Chaffinch, and Siskins. Slice and spear apple onto tree branches and you may be rewarded with a sighting of the fruit loving Waxwing and Blackcap. Keep an eye out for the UKs smallest bird, the Goldcrest, weighing it at a mere 6g! They are very distinctive with their yellow/gold strip down their head. They are insect eaters so will often be seen flitting amongst bushes catching small bugs and flies.


In Focus- Grey Seal Pups

Seems a strange time of year of any animal to decide to start giving birth, especially a marine animal just as the strong winds and storms start to blow through tossing up the sea. But there is method in the madness it seems, after a full summer of feasting on rich oily fish the mothers are in the best shape to give birth and suckle their young.

Grey Seal mum and pup.
Copyright Rob Fray
Newborn Grey Seal pup.
Copyright Rob Fray
Grey Seal pup.
Copyright Rob Fray

Grey seal pups are born on quiet, often remote beaches. The mothers haul themselves up onto the beach to give birth to their white fluffy young. The young will stay on this beach suckling their mother’s rich milk for around a month in which time they can put on 30kg in weight every 2 weeks. While the mothers are busy with their young, the male Grey Seals, who can weigh up to 300kg and grow to 2metres in length, stalk the beach fighting with other males to keep their territory and ‘harem’ of females. Once the females have finished suckling their young, they will mate with the dominant male before heading back to the sea leaving their pups alone on the beach. They will stay here for around another 2 weeks while they moult their white fluff and become brave enough to head out into the unpredictable winter seas.

Seals have been the subject of persecution in the past, especially the young Grey Seal pups whose white skins were highly priced. For this reason, seals are protected under the Marine (Scotland) Act 2010. This Act allowed Scottish Ministers powers to designate seal haul-out sites and protect them under the Protection of Seals (Designation of Haul-Out Sites) (Scotland) Order 2014. There are currently 47 designated seal haul-out sites in Shetland where it is an offence to intentionally or recklessly disturbed or harass seals.


Moth of the Month- Rosy Rustic

It is getting pretty late in the year for moths but with favourable weather and light winds the Rosy Rustic (Hydraecia micacea) is one of the few that will still be seen in the moth trap. They are a common resident flying from August-October. There size can vary greatly with females generally being larger and darker. The forewings are pointed and pinkish/brown with a rather velvety texture and darker margins in the centre. Adults will lay their eggs on the food plant (a low growing plant such as docks, potatoes, horse tails and yellow iris) before dying off. The eggs overwinter with the larva hatching in April, pupating underground without a cocoon before emerging as an adult in August.

Rosy Rustic
Copyright Rob Fray

In other news…

One of the more curious birds to arrive in October is the Great Grey Shrike (Lanius excubitor). They have grey backs, white underbellies and black and white markings on the wings and tail. Their most distinctive feature is their black mask and sharp hooked beak, giving them their nickname the ‘masked assassin’.

What makes these guys so interesting is their feeding habits. They are predatory, hunting small mammals, birds and lizards which they beat to death with their beaks. In Shetland they often hunt on Goldcrests which are passing through in high numbers at this time of year. They are lone hunters, sitting in wait on a vantage point such as a fence post. They can even imitate other birds calls to try and lure its prey closer. Now for the gruesome bit…once they have made a kill they will cache it for later by impaling it onto thorns and branches within a bush hidden from other predators.

Great Grey Shrike.
Copyright Rob Fray

As they are members of the passerine (songbird) family they have weak feet that are not designed for holding their prey, by impaling it onto a thorn or stick they can use this to secure the food while they use their beaks to pull it apart and devour it. So, if you happen to spot a bush adorned with small dead birds, you’ll know there is a Great Grey Shrike not far away!



September Highlights

It is starting to feel very autumnal now we are into September. The sun seems to be only glimpsed on occasion, the wind is back and there is a chill in the air. It will soon be time to click the heating on and get the fire lit.

Much of the birdlife has already started to move on. The seabirds were the first to leave, the cliffs at Sumburgh head are all bare now that the Puffins, Guillemots and Razorbills have left to spend the winter at sea although you may still find Fulmars and Gannets with large young still in the nest. The insect life in the garden will be getting less too as species such as the bumblebees, moths and butterflies migrate or look for a cosy place to hibernate over the winter.


In Focus- Autumn Migration

September is the peak month for the autumn bird migration in Shetland where the birds, having finished breeding, are heading back to their wintering grounds crossing through Shetland en route. During favourable weather conditions (easterly winds) large numbers of migrants and even some vagrants (birds who have been blown off course) can appear in Shetland. Some more memorable visitors have included: Siberian Rubythroat, Chestnut-eared Bunting and Siberian Accentor. Remember to provide a shallow dish of water, as many of these birds have flown a long away and will be thirsty as well as hungry.

Siberian Accentor
Copyright: Rob Fray

Some of the more difficult migrants to identify are the Warblers as many species can be very similar in appearance. Warblers are mostly insect eaters and may be seen flitting between bushes and shrubs in the garden catching small bugs. I will introduce you to a handful of the more common species but if you are unsure of an ID and have managed to get a photograph you can email it to us at shetlandcommunitywildlife@outlook.com or if you are on Facebook, post it on the Nature in Shetland Photos group where there are a lot of local enthusiasts who can help.


Willow Warbler (Phylloscopus trochilus)

The Willow Warbler is a small warbler (10.5-11.5cm) with a pale underbelly and a green/grey upper body and wings. As many of the individuals passing through in Autumn are juveniles, they tend to be brighter yellow in colour. They have a light-yellow stripe above the eye. They are very similar in appearance to the Chiffchaff but have pale pink legs. Willow Warblers are earlier migrants than the Chiffchaff, commonly seen in early September.

Willow Warbler
Copyright: Rob Fray

Chiffchaff (Phylloscopus collybita)

Chiffchaffs are a similar size (10-11cm) to Willow Warblers but have a more olive-brown colouration, a paler eye stripe and dark grey-black legs. They flit quickly between branches and when stationary express a distinctive tail-wagging behaviour which Willow Warblers do not. Chiffchaffs arrive towards the end of September through until early November.

Chiffchaff
Ken Billington / CC BY-SA

Yellow-browed Warbler (Phylloscopus inornatus)

The Yellow-browed Warbler is another small warbler, slightly smaller in size to the Willow Warbler and Chiffchaff. They are a little easier to identify than the previous two: they are greenish brown in colour with a pale underbelly, they have a thick, distinctive eye stripe which gives them their ‘yellow-browed’ name and two light coloured wing bars. Formerly, the Yellow-browed Warbler was a very scarce migrant but in recent years they have appeared in much greater numbers to the extent that in late September they are now often the most common migrant warbler in Shetland.

Yellow-browed Warbler
Copyright Rob Fray

Other warblers passing through this month include: Lesser Whitethroat, Garden Warbler and Barred Warbler.


Moth of the Month- Square-spot Rustic

The number of moths flying and coming to the moth trap will be starting to slow down this month as the colder, windier weather of the Autumn starts to come in. One of the later flying moths that is common into September is the Square-spot Rustic (Xestia xanthographa). They get their name from the rather conspicuous square kidney shaped mark on the forewings. Colour can vary from shades of red, grey and brown. I often see the reddish/chestnut colouration which I think is especially pretty.

They are sugar eaters and can be seen feeding on plants such as Ragwort, Heather and Marram. Some years they are seen in large numbers, best seen at dusk over grassland areas.


In other news…

There are a handful of different dolphin species that can be spotted around the Shetland coast. Risso’s Dolphins are resident in the isles and are the most commonly seen. Atlantic White-sided Dolphins are rare vagrants but when they do arrive, they are often in what is known as a ‘super pod’ of 50-100 individuals. White-beaked Dolphins are resident, but sightings are reasonably rare.

Risso’s Dolphin (Grampus griseus) are a large species of dolphin growing up to 4m in length. They are what is known as a beakless dolphin as they have a bulbous square-shaped head. They are dark in colour but become whiter with age, mature animals are often covered in many scars and scratches. These scars come about from fights with other Risso’s and from their favourite prey- squid. Individuals animals can be identified by their unique pattern of scars. They can appear in groups of 50+ individuals although in Shetland, groups of over 20 are rarely seen.

Risso’s Dolphin with calf
Copyright: Rob Fray