Thursday, September 28, 2017

Home From Skiathos

Sue and I are back from Greece and as usual, up to our ears in catch-up with friends and family. Until I get up and running with birding I put together a few pictures of the last two weeks in Skiathos. Please "click the pics" for better views.

Two weeks of late September wall-to-wall sunshine, temperatures in the thirties and not a cloud in the deep blue Skiathos sky. I found myself feeling increasingly uncomfortable with the almost total lack of birdlife during what should be a period of peak migration. Yes, we saw House Sparrows, Collared Doves, swallows, and hundreds of the ubiquitous Hooded Crow and Yellow-legged Gull but had to search hard to find the limited number of migrants hiding from the burning midday sun. 

Nr Ligaries, Skiathos

Agia Paraskevi, Skiathos

The Bourtzi, Skiathos Town

The Bourtzi, Skiathos Town

Skiathos Town

The ferry - Skopelos to Skiathos and vice versa 

Where to go - Skiathos Town

 Coffee Time - Skiathos Town

I have experienced this strange sensation before on Skiathos and also on islands such as Menorca, Lanzarote, and closer to home on Bardsey Island and North Ronaldsay. Such times reinforce the understanding of the effect of the weather on bird migration during spring and autumn when theoretically there should be migrant birds at every turn but when ideal holiday weather makes for poor birding. A drop or two of overnight rain or preferably one of the famous Skiathos thunderstorms would have made for interesting mornings but it was not to be. 

It was in the relative cool of the hills and the monastery gardens that we found Spotted Flycatchers together with small numbers of Willow Warblers, Chiffchaffs, Blackcaps, Garden Warblers and Eastern Olivaceous Warblers. Up here close to the pine forests we saw Honey Buzzards circling and small numbers of Bee Eaters and swallows, both Common and Red-rumped. 

Church at Evangelistria
To the Monastery

Spotted Flycatcher
Willow Warbler

Red-backed Shrike

Red-rumped Swallow

Hooded Crow

Unlike our own farmland Barn Swallow the Red-rumped Swallow is a bird of the open hilly country of southern Europe and Asia where they build quarter-sphere nests with a tunnel entrance lined with mud collected in their beaks. They normally nest under cliff overhangs in their mountain homes, but will readily adapt to buildings and bridges. 

Red-rumped Swallow

It doesn’t matter where you go in Skiathos. There’s always a Red-backed Shrike to enliven proceedings and inevitably one that lacks any red in the plumage but displays the autumn russets of a juvenile or female.

The Red-backed Shrike is a very common bird in all of Greece and the Greek Islands, and a bird well known to Aristotle, the original Greek birder. The Latin/scientific name of the Red-backed Shrike is Lanius collurio, the genus name, Lanius derived from the Latin word for "butcher" and the specific collurio is from Ancient Greek “kollurion”. 

Red-backed Shrike

Red-backed Shrike

In the pine forests there are fire crews on permanent watch to ensure that help quickly reaches any conflagration. A few years ago forest fires in mainland Greece spread by strong winds across the waters of the Aegean to the islands of Skiathos and Skopelos where they devastated huge swathes of forest and claimed many lives. Only now have the forests recovered. 

Fire Crew - Skiathos

Our forest dwelling Jimny

Spotted Flycatcher

From the forested Kanapitsa peninsula of Skiathos it is possible to see the church of Agios Ioannis Kastri out towards the neighbouring island of Skopelos and where scenes of Mamma Mia were filmed. The film runs through the summer season in the open air cinema in Skiathos Town. The church stands on top of a rock and provides amazing view to the coasts of Skopelos and to Alonissos. Its name actually means Saint John on the Castle, assuming that probably there was a small castle there in the past to protect the island from pirates.

The "Mamma Mia" church of Agios Ianiss Kastri

Open Air Cinema - Skiathos Town

Me? I'd rather be birding than watch that awful film. Log in soon for more birding.

Linking today with Eileen's Blog and Anni's Birding.

Wednesday, September 20, 2017

Home from Home

Sorry there’s no recent news. Sue and I are in Skiathos, Greece for a few days. Back soon but in the meantime there are pictures from recent years in Skiathos. Enjoy, and don’t forget to “click the pics” of Skiathos and its birds. 

 Skiathos - centre right

Red-backed Shrike

Hooded Crow


Yellow Wagtail

Skiathos Town

Skiathos Town

Skiathos Town


Isabelline Wheatear


Little Egret

Yellow Wagtail

To The Beach

 Alonisos -Skiathos

Skiathos - Kastro


Woodchat Shrike

Eleonora's Falcon

Red-backed Shrike

European Shag

Koziakis - Skiathos Town

View towards Skiathos Town

Let's finish with a video of Skiathos. It features the headland of Kastro where the Eleonora's Falcons spend the summer months . Enjoy.   

Back soon.

Tuesday, September 12, 2017

A Smelly Old Business

How do birds navigate over long distances? This complex question has been the subject of debate and controversy among scientists for decades, with Earth's magnetic field and the birds’ own sense of smell among the factors said to play a part.

It’s a subject discussed previously on Another Bird Blog but here's an interesting update by way of scientific experiments on an island I know very well.

In new investigations researchers closely followed the movements and behaviour of 32 Scopoli's Shearwaters Calonectris diomedea off the coast of Menorca. 

Scopoli's Shearwaters breed across the Mediterranean on Menorca, Ibiza, Formentera, Cabrera, Conillera and Dragonera. The majority of the population of Scopoli's Shearwater spend the non-breeding season in the Atlantic, including areas off the west coast of Africa and east coast of Brazil. They return to the Mediterranean in spring where they breed on rocky coasts and offshore islands, often close to or alongside Balearic Shearwaters Puffinus mauretanicus.  Hence, I see both species of shearwater when I visit Menorca in early May each year and when both are clearly visible from the shore, numbers varying with the daily weather conditions.

 Scopoli's Shearwater  - Daniele Occhiatto

Baearic Shearwater -Marcabrera [CC BY-SA 2.0], via Wikimedia Commons 


Now, researchers from the universities of Oxford, Barcelona and Pisa have shown in a new experiment that the sense of smell (olfaction) is almost certainly a key factor in long-distance oceanic navigation, eliminating previous misgivings about this hypothesis. 

For the experiment the birds were split into three groups: one made temporarily anosmic (unable to smell) through nasal irrigation with zinc sulphate; another carrying small magnets; and a control group. Miniature GPS loggers were attached to the birds as they nested and incubated eggs in crevices and caves on the rocky Menorcan coast. But rather than being displaced, they were then tracked as they engaged in natural foraging trips. 

Study leader Oliver Padget, a doctoral candidate in Oxford University's Department of Zoology, said: "Navigation over the ocean is probably the extreme challenge for birds, given the long distances covered, the changing environment, and the lack of stable landmarks. Previous experiments have focused on the physical displacement of birds, combined with some form of sensory manipulation such as magnetic or olfactory deprivation. Evidence from these experiments has suggested that removing a bird's sense of smell impairs homing, whereas disruption of the magnetic sense has yielded inconclusive results"

"However, critics have questioned whether birds would behave in the same way had they not been artificially displaced, as well as arguing that rather than affecting a bird's ability to navigate, sensory deprivation may in fact impair a related function, such as its motivation to return home or its ability to forage. Our new study eliminates these objections, meaning it will be very difficult in future to argue that olfaction is not involved in long-distance oceanic navigation in birds."

All birds went out on foraging trips as normal, gained weight through successful foraging, and returned to exchange incubation periods with their partners. Thus, removing a bird's sense of smell does not appear to impair either its motivation to return home or its ability to forage effectively. However, although the anosmic birds made successful trips to the Catalan coast and other distant foraging grounds, they showed significantly different orientation behaviour from the controls during the at-sea stage of their return journeys. 

Scopoli's Shearwater - Martin Garner

Instead of being well-oriented towards home when they were out of sight of land, they embarked on curiously straight but poorly oriented flights across the ocean, as if following a compass bearing away from the foraging grounds without being able to update their position. Their orientation then improved when approaching land, suggesting that birds must consult an olfactory map when out of sight of land but are subsequently able to find home using familiar landscape features. 

Senior author Tim Guilford said: "To the best of our knowledge, this is the first study that follows free-ranging foraging trips in sensorily manipulated birds. The displacement experiment has rightly been at the heart of bird navigation studies and has produced powerful findings on what birds are able to do in the absence of information collected on their outward journey. But by its nature, the displacement experiment cannot tell us what birds would do if they had the option of using outward-journey information, as they did in our study. This heralds a whole new era of work in which careful track analysis of free-ranging movements, with and without experimental interventions, can provide inferences about the underlying behavioural mechanisms of navigation. Precision on-board tracking technology and new analytical methods, too computationally heavy to have been possible in the past have made this feasible."

Story Source: University of Oxford. "Sense of smell is key factor in bird navigation, new study shows." Science Daily, 29 August 2017.

Linking today to Stewart's World Bird Wednesday.

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