Tuesday, 26 November 2019

Meisen Wood: The Great Oktoberfest


Temperature: 28C to 4C
Precipitation: much!
Ringers:  CS and EB
Sound: Great Tit, Redwing & Goldcrest

Species
Ringed
Re-trapped
Total
Blackbird
2

2
Blackcap
1

1
Blue Tit
35
12
47
Chaffinch
3

3
Chiffchaff
2

2
Coal Tit
11
3
14
Dunnock
1

1
Firecrest
8

8
G S Woodpecker

1
1
Goldcrest
256
3
259
Great Tit
342
56
398
Greenfinch
3

3
Jay
1

1
Marsh Tit
2
6
8
Nuthatch
4
5
9
Redwing
62

62
Robin
6
2
8
Short T Treecreeper
2
1
3
Song Thrush
1

1
Treecreeper
1
1
2
Wren
3

3
Total
746
90
836

Oktoberfest: an icon of German culture enjoyed by thousands each autumn.  At these mega – beer festivals copious quantities of golden - amber beer with frothy white heads is served, in large steins or tankards, to joyous crowds delighting in other German traditions and good banter.  The original Oktoberfest, in Munich in 1810, was part of the marriage celebrations of Bavaria’s Crown Prince Ludwig to Princess Therese of Saxony-Hildburghausen.  This evolved into an annual event which in its early years had the atmosphere of a fairground coupled with horse racing; later it included an agricultural show too.  In those years beer was served at small stands.  From the 1860s onwards the beer stands were replaced by beer tents and the emphasis was switched to a celebration of beer.  Today the Munich Oktoberfest (others are available) is usually sixteen days of homage to the marriage of the grain and the hop, and beer tents have seating capacities for several thousand quaffers.

In Meisen Wood we have no such revelries, though in this season ringing sessions often end with a mug of hot chocolate liberally laced with rum; or a glass, or two, of glühwein.  Though we do have our own Oktoberfest – a festival of colour! 

October in our wood, like many woods, is a colourful delight.  The trees are dressed in multiple tones of greens, reds, yellows, oranges; and yes, attractive browns while the larches are an incandescent gold.  Throughout the month, and on into November, these tints and tones provide a living tapestry of ever changing hues: a rich statement of spectral boldness to the season’s passage.  And when the wind blows the falling, twirling, spinning, twisting leaves are a spectacular kaleidoscope.  We do not perceive this colourful event as the season’s protracted death throes but as the essential transfer of matter and energy from one trophic level to another; an integral component of the recycling of elements that sustain life.  This arboreal display is augmented by fungi and birds.  The reds and browns of agarics and boleti, the bright whites of inkcaps and mushrooms, the yellows and oranges of coral fungi add colour to the woodland floor.  And birds flitting through the trees provide fine flecks of colour.



Typically October’s totals are the year’s highest, though September’s and March’s figures are not much less.  This October was no different but attaining the totals, shown in the table, was challenging because of persistently wet weather.  Indeed, we only completed one full session though it yielded 167 new birds including a 133 new Great Tits.  Fortunately CS, courtesy of retirement’s liberation, was able to open some nets on numerous occasions while playing dodgems with the downpours.

A confession: we are rather fond of Great Tits.  We admire their riotous yellows, greens, blues, and contrasting tones of black and white.  With a Great Tit in hand one can appreciate the tonal shifts in yellows on their breasts and abdomens, and how these colours transcend and fuse into the greens of the bird’s body; an exotically coloured bird, which is probably a real challenge to the artist’s palette.  Rather fond implies reservations these do exist with this small but often aggressive bird.  Its antagonistic behaviour, particularly at feeders, is not always endearing as, presumably dominant males, viciously attack sub-ordinates; on two occasions we have witnessed the killing of conspecifics.  But then such behaviour is a component of the bird’s biology which allows it to successfully fill its niche, and, as unpalatable as it may seem, Nature is red in claw and bill. 

Through October Great Tits were targeted.  September’s and October’s combined total is a very pleasing 583 new Great Tits ringed.  So why target Great Tits?



In 2018 it became apparent that there was a movement of Great Tits, for about six or seven weeks, along the Teutonburger Hills.  We are curious to know if this is an annual migration or periodic dispersion; is it equal in intensity each year; and where are the birds coming from and wither do they wonder?  Hopefully this year’s data combined with last year’s data and future data will provide some interesting answers. 

Continental Great Tit populations are described as being: sedentary, partial migrants, migrants, are occasionally irruptive, and display extensive juvenile dispersal.  Well, that covers all the possibilities of avian migratory movements.  In all probability Great Tits are a mix of those possibilities.  Research indicates that Great Tit movement, including migration, is an integrated response to population density; and food and nest cavity availability.  Also, Great Tit’s show a hierarchy in their movements: dominant males, adult females, then juvenile males, and juvenile females.  The dominant males stay on territory, or nearby in an endeavour to secure prime territory and thus breed successfully the following year; while juvenile females are the most likely to be forced into dispersal and migratory movements.

The German Migration Atlas indicates that most summer captured adult Great Tits are sedentary; and there is substantial juvenile dispersal which can be over large distances.  Further, there is an autumnal influx of Great Tits from the Baltic States with many of those individuals moving on to the Netherlands, Belgium and northern France. Similar studies in the Baltic States demonstrate a regular autumn passage, particularly of juvenile females, away from the region.  These later studies indicate a strong correlation between population density and food availability and that Great Tit movements show a degree of periodicity i.e. have a cyclic pattern which is not necessarily annual.

So, what does our data indicate?  Adults comprised 4.7% of the whole catch and this was split equally between males and females.  The remaining captures, all juveniles were: 40% males and 60% females.  This is similar to last year’s results where the juvenile cohort was 37% and 63% males to females. This difference is probably statistically significant and conforms to the findings in the Baltic States.

Last autumn’s Great Tit cohort has provided five controls from four birds in the Netherlands.  One Great Tit was controlled, two days after be ringed by us, at a nearby Dutch ringing station, 43km from here.  The others were controlled in an area between Arnhem and Maastricht averaging 130km from here.  One of the controls is particularly interesting as it was initially controlled in December, then again at the same site in early March.  Therefore was it in its wintering area or was it passing through on both occasions?

Hopefully this year’s cohort will provide a similar number of controls.  And already we are looking forward to another Great Tit Oktoberfest in efforts to establish if this exotically coloured bird is a regular migrant along the Teutonburger Hills and whether this movement show periodicity?  Bring on next year’s Oktoberfest; um, maybe its time to go to Munich for a few days too, to try the real thing! 

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