Bright n' windy. 455 Cormorant went out early with another 350 coming in from the north nearly an hour later. Southbound 20 Red-throated Diver, 3 Shelduck & 2 Brent with northbound 6 Red-throats, Guillemot & Shelduck. 9 Common Scoter were sat offshore. This is only our second Guillemot record of the year with the previous one back in January - last century they were offshore in small numbers all winter with fewer and fewer being noted over the years.
Migratory movements of bats are shaped by barrier effects, sex-biased timing and the adaptive use of winds
For those interested in bat migration, which we have been involved with, have just received the below from Sander in The Netherlands :-
We just published a paper in Movement Ecology on bat migratory movements in the southern North Sea area.
How ecological barriers like the North Sea affect bat migratory movements is still poorly known. In 2021 and 2022 we tagged 44 Nathusius’ pipistrelles (Pipistrellus nathusii) on the East coast of the United Kingdom (UK) and investigated their movements to continental Europe using the MOTUS Wildlife Tracking System.
Our study demonstrates that bat migratory movements are highly influenced by barrier effects, sex-biased timing of migration and the adaptive use of winds.
➡️ Barrier effects cause migratory movements along the coast, and crossings over sea are shortened by deviating from the general migration direction.
➡️ In spring males migrate later in the season than females.
➡️ The overall migration speed of females was 61 km/day, and 88 km/day after their last detection in the UK
➡️ Bats use wind adaptively to reduce airspeed when flying under tailwind and increase airspeed when flying under crosswind conditions.
➡️ Departures over sea coincidence with tailwinds, enabling bats to more than double their airspeed, reaching groundspeeds of up to 16.8 m/s (60.5 km/h).
➡️ Our analysis suggests that bats select altitudes with favourable wind conditions and that they seek altitudes of several hundred meters, possibly extending up to 2,500 m.
➡️ Low-altitude migration occurs when wind conditions are less favourable , e.g. during generally low wind speeds and in response to increasing headwinds or crosswinds at higher altitudes.
To our best knowledge this is the first study to estimate flight altitudes using 2 D tracking data.
The results of our study contribute to a more comprehensive understanding of the decision-making process and adaptations bats employ during their migration.
Elucidating bat migration patterns will enable us to develop effective conservation measures, for example in relation to the development and operation of coastal and offshore wind farms.
You can access the paper here https://lnkd.in/gePCDPFU.
We dedicated this paper to the memory of Ommo Hüppop, who co-authored this paper.
Kind regards,
Sander Lagerveld, Pepijn de Vries, Jane Harris, Sue Parsons, Elisabeth Debusschere, Vera Brust and Heiko Schmaljohann
The paper can also be accessed by copying & pasting this to your search engine -
https://movementecologyjournal.biomedcentral.com/articles/10.1186/s40462-024-00520-7
Ringing: 1 House Sparrow.
Ringing: 1 Blackbird.
Ringing: 1 Chaffinch.
Ringing: 2 Blackbird.
With the weather deteriorating the moth traps were finally packed away for the winter
Dull, but fairly mild morning. Worth a mention are single Fieldfare & Woodcock. Brief offshore observations were southbound 16 Wigeon & a Pintail.
267 birds of 23 species is similar to recent years totals. Late Willow Warbler is worth highlighting. Redpoll numbers have been pathetic this year with Long-tailed Tit obviously having a poor breeding year as this flock was the only volery to appear all autumn.
Ringing: 7 Blackbird.
Ringing: 2 Blackbird.
Ringing: 1 Blackbird
Ringing: 1 Blackbird.
Ringing: 3 Blackbird, 1 Redwing, 1 Robin.
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Ringing: 4 Blackbird.
Black-headed Gull ringed LBO 15th January 2010 and seen every winter either at LBO or Felixstowe Pier up to 25th February 2023 was at several sites in Gdynia, Poland from 18th January to 26th March 2024, has now been seen 1,504 km away at Talska (ereras), Siauliai, Lithuania on 29th October 2024. Having wintered in Felixstowe for 13 years, Poland last winter & now seen in Lithuania one wonders where its going to go this winter ?
Blackbird ringed Sandwich Bay, Kent 14th January 2024 was retrapped 74 km away at LBO on 16th November 2024. Presumably a continental bird that winters in the UK coming in via a different route this winter ?
Cold wet morning dampened the enthusiasm levels some what not helped by nothing moving offshore. 402 Cormorant headed out fishing in the gloom early on. From a sparse selection of records worth a mention are 3 Song Thrush, 2 Woodcock, Little Egret plus Purp & Rock Pipit on the point.
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Ringing: 5 Lesser Redpoll, 1 Blackbird, 1 Song Thrush.
Handful of new Blackies, Songies plus 2 Lesser Redpoll was as good as it got around the observatory. Offshore movements sparse with southbound 9 Black-headed Gull, 7 Brent, 2 Great Crested Grebe, 2 Snipe, Little Egret & Red-throated Diver with northbound 5 Gannet, 4 Brent & a Red-throat. Those togger friendly 3 Purps were at the point although the English Dictionary is yet to catch up with the current usage of this term.
Ringing: 2 Blackbird, 2 Lesser Redpoll, 1 Song Thrush.
Birds Ringed: Blackbird 6, Goldcrest 1, Wren 1.
Ringing: 16 Blackbird.
Ringing: 4 Blackbird, 2 Blackcap, 2 Song Thrush, 1 Chiffchaff, 1 Goldcrest, 1 Redwing.
