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1 April 2008 Ornithology from the Tree Tops
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The decline of the Black-tailed Godwit in The Netherlands is inversely proportional to the attention heaped upon the species by birdwatchers, conservationists and governmental agencies. The number of pages devoted to Dutch Godwits, or meadowbirds in general, must run in the 10 000s. An incomplete survey of research papers dealing with meadowbirds up to 1984 mentioned 329 reports and papers (Verstrael 1987), and the stream of - unfortunately mostly grey - literature has continued unabated. Nevertheless, the trend of Godwits in the 20th century is poorly documented. Based on changes in land use and farming practices, we can only hypothesize about the trend up to the late 1960s. Probably increasing, according to qualitative statements of farmers and birdwatchers, hinting at the increased food supply in the footsteps of the introduction and large-scale use of artificial fertilizers. Quantitative date became available in 1972, when Theo Mulder published a detailed treatise on the Dutch Godwits, including the first attempt to arrive at a countrywide estimate, for 1967 that is. His exercise is well-documented, naming study sites, surface areas of grassland investigated and available, stratifying habitats, real densities and conversions. In the present age of indices, partly (and sometimes largely) based on imputed figures for missing values and impossible to evaluate by independent researchers, a relief to read (Mulder 1972). Another remarkable feature of his treatise: the population was considered stable in prime habitat (peat district) and even increasing in less optimal (clay) and marginal (sand) districts. The estimate by Theo Mulder has become the focal point for later estimates, although - as far as I know nobody tried to validate his primary data and methods. In the years to follow several other attempts at estimates were published, based on the activities of the growing birdwatcher community using more or less standardised census methods.

Even so, it took a distress call as late as the year 2000 to bring home the message that Godwit numbers were plummeting over vast stretches of their Dutch breeding grounds (Altenburg & Wymenga 2000). Up till then, indices produced by SOVON seemed to indicate that Godwits - after a decline in the early 1970s - had been stable for the past 25 years (reproduced in Bijlsma et al. 2001). How was this possible, in the face of the glaring decline? For one, it is easy to produce trend indices, but it takes a critical field-based attitude to evaluate the validity of indices. Secondly, it is of utmost importance to use more than just one monitoring method. Relying on a single method, as in The Netherlands, is asking for trouble, because independent checks via other methods are not available (or used), and any discrepancy with reality is likely to go undetected. The SOVON-produced trend for the Black-tailed Godwit up to 2000 is a point in case. It took hard-core, mud-covered fieldworkers to point out what the real Godwit world looked like: not good at all…

Is producing reliable trends already difficult, effectively protecting the species turned out to be nigh impossible. Six years after their first outcry, Altenburg & Wymenga (2006) produced another, evaluating the steps taken in between to protect Godwits and their habitat. The message is clear: intentions are good, full-colour action plans abound, research continues, forces are joined, subsidies provided, bottlenecks identified, media alerted, reserves created, and ‘Godwit galas’ organised, but Godwits decrease ever more rapidly and conservation money is wasted in suboptimal or marginal Godwit habitat. In short, the virtual reality of Godwit protection continues to exist, albeit with different players. Nothing new here (Hettema 2004). Actually, the situation has gone from bad to worse, because protection is nowadays muddled by funnelling money into the right pockets, and keeping jobs alive. Also, the focus has partly shifted to predation, in itself only a derivate of problems associated with farmland management. And finally, where have all the Lapwings and Skylarks gone?

The present situation is as follows. Our Godwits spend the winter mostly in Guinea-Bissau where they forage on spilt rice. Return migration commences in late February and March, and the birds may use stopovers in rice complexes in Portugal and Extremadura to fatten up again. Arriving in The Netherlands in good condition, the meadows in peat- and clay districts are still sufficiently attractive to initiate settlement and egg laying. From here, problems mount. Present-day dairy farming allows for early and repeated mowing, actually weeks earlier than a century before. This has converted Godwit habitat into an ecological trap, where near-annually the majority of nests or chicks is killed by mowing. This massacre is clearly visible on the post-breeding roosts, where Godwits congregate prior to migration. Normally visited from early July onwards, after the chicks have reached independence, nowadays large numbers of Godwits can be found on the roosts in early or mid-May, all of them adults in breeding plumage (Kleefstra 2005). This signifies an advancement of more than a month compared with the late 1960s. Failing reproduction lies at the heart of Godwit decline, not changes in wintering grounds nor a change in survival (possibly even improved after legal protection in southern Europe led to a concomitant decline in mortality from shooting along the migratory pathway; Kuijper et al. 2006).

Imagine the individual Godwit, growing old and commuting back and forth between Guinea-Bissau and Frisia, only to have its breeding attempt thwarted again by industrial farming. Not once, but year after year. A sad reminder of an affluent society unable to protect life forms other than human. In the words of Haverschmidt (1963): “The situation in Holland is thus by no means secure and it depends entirely on ourselves if we are to keep our country as a stronghold for our meadow birds.” After half a century of meadow bird protection, the conclusion is that we utterly failed.

References

1.

W. Altenburg & E. Wymenga 2000. Help, de Grutto verdwijnt! De Levende Natuur 101: 62–64. Google Scholar

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W. Altenburg & E. Wymenga 2006. Help, de Grutto verdwijnt! - II. De Levende Natuur 107: 98–99. Google Scholar

3.

R.G. Bijlsma , F. Hustings & C.J. Camphuysen 2001. Algemene en schaarse vogels van Nederland. (Avifauna van Nederland 2). GMB Uitgeverij/KNNV Uitgeverij, Haarlem, Utrecht. Google Scholar

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F. Haverschmidt 1963. The Black-tailed Godwit. Brill, Leiden. Google Scholar

5.

H. Hettema 2004. Grundrecht voor de grutto. It Fryske Gea/Uitgeverij Noordhoek, Leeuwarden. Google Scholar

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R. Kleefstra 2005. Grutto's jaar na jaar te vroeg, massaal en zonder kroost op Friese slaapplaatsen. Twirre 16: 211–215. Google Scholar

7.

D.P.J. Kuijper , E. Wymenga , J. van der Kamp & D. Tanger 2006. Wintering areas and spring migration of the Back-tailed Godwit: bottlenecks and protection along the migration route. A&W-report 820. Altenburg & Wymenga ecological consultants, Veenwouden. Google Scholar

8.

T. Mulder 1972. De Grutto in Nederland. Wetenschappelijke Mededeling KNNV nr. 90. KNNV, Hoogwoud. Google Scholar

9.

T. Verstrael 1987. Weidevogelonderzoek in Nederland. Contactcommissie Weidevogelonderzoek van de Nationale Raad voor Landbouwkundig Onderzoek, 's-Gravenhage. Google Scholar
Rob G. Bijlsma "Ornithology from the Tree Tops," Ardea 96(1), 1-2, (1 April 2008). https://doi.org/10.5253/078.096.0101
Published: 1 April 2008
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