This
is a ‘saguaro boot’. Let me explain what it is. Two species of woodpecker, Gilded
Flicker (Colaptes chrysoides) and Gila
Woodpecker (Melanerpes uropygialis)
have adapted to live in arid desert environments in the SW USA and NW Mexico.
Both species excavate nest holes in the fleshy trunks and limbs of saguaro cacti,
but the plants treats these intrusive cavities as wounds and react by secreting a lignin sap that hardens
around the hole chambers, effectively making protective sealing shell. Cleverly,
the woodpeckers do not use the holes until the following year, waiting until
the sap has dried out and the scar tissue of the chamber wall has become solid
and watertight. When a cactus dies, its outer flesh rots away, but the tougher
woody interior and the callus around any holes remain. These shells are angular
in shape, keeping the form of the entrance and the chamber of the woodpecker cavity.
These so-called ‘saguaro boots’ can be
found on the ground amongst the debris of dead cacti. Interestingly, the boot in
this photo is a double one! Thanks to Noel Snyder for sending me this remarkable image
from Arizona, USA.
Wednesday, 6 December 2017
Friday, 29 September 2017
Wednesday, 27 September 2017
Saturday, 2 September 2017
Wednesday, 16 August 2017
Andean Flicker on the cover
The latest issue of Neotropical Birding, magazine of the Neotropical Bird Club, has a great photo of female Andean Flicker (Colaptes rupicola) on the cover.
Saturday, 3 June 2017
Saturday, 20 May 2017
WOODPECKER - a new book
A new book entitled simply WOODPECKER is due to be published this summer by Reaktion Books, London, in their acclaimed Animal Series. Written by Gerard Gorman the book examines not only the natural but the cultural history of the animal... how it has been viewed by people from ancient times to the present day, and examines the woodpecker in art, literature, media, religion, mythology, legend and folklore.
Tuesday, 7 March 2017
Wednesday, 22 February 2017
Friday, 17 February 2017
Ground Woodpecker - habitat and nest holes
The Ground Woodpecker (Geocolaptes olivaceus) is a woodpecker which does not peck wood. It is arguably the most terrestrial woodpecker species on the planet, rarely seen near trees. Here is an image of its habitat and an earth bank with nesting holes (see very top right of the bank). This species is endemic to southern Africa (South Africa and Lesotho), where it is not uncommon locally. This location was in the Sani Pass in SA at around 2500m above sea-level (Gerard Gorman).
Friday, 20 January 2017
A NEW BOOK WITH WOODPECKER CONTENT
A REVIEW OF AN IMPORTANT NEW BIRD GUIDE WITH WOODPECKER CONTENT
BIRDS OF THE INDONESIAN ARCHIPELAGO: GREATER SUNDAS
AND WALLACEA
by James A. Eaton, Bas van Balen, Nick W.
Brickle & Frank E. Rheindt.
Published in November 2016 by Lynx Edicions,
Barcelona, 2016. Hardback. 65 Euros.
This book is the first field guide to cover all the
birds found in the Indonesian archipelago. This huge and ornithologically
diverse area includes the islands of Sumatra, Borneo, Java and Bali (the
Greater Sundas), and Sulawesi, the Moluccas and the Lesser Sundas (Wallacea)
and the smaller islands amongst them. These two regions, divided by the
Wallace’s Line, are shown inside the book in large and very helpful maps: the
Greater Sundas inside the front cover and Wallacea inside the back.
A grand total of 1,417 bird species are covered in
the book’s 496 pages. The comprehensive nature of the work means that, in addition
to the region’s 601 endemics, the authors also detail 98 vagrants and eight
non-native, introduced species. Every subspecies (race) is also described - a
remarkable achievement by the authors. Many readers and reviewers, including
myself, will occasionally question some of the taxonomic decisions made and
thus the taxons included, but this is inevitable given the current state of
avian taxonomy where no definitive list is agreed upon. It is enough to say
here that the authors are very well-versed in today’s taxonomic issues and
debates and made their decisions on what to include or omit, as species or
subspecies, accordingly.
The text is backed-up by around 2,500 illustrations
and 1,339 distribution maps. The concise texts on species are directly opposite
the colour plates which also have the distribution maps included on them. All
very convenient and ideal for use in the field. Although essentially a field
guide, an introduction of sixteen pages, a bibliography of six and an index of
sixteen, add to its weight and size, but this is inevitable for the book to be
as comprehensive as it is and given the number of birds it deals with.
Having a keen interest in the Picidae, upon
receiving the book I at once turned to the woodpeckers on pages 206 to 214. The
first thing that struck me was that the illustrations were very familiar.
Perhaps I was naïve, but I was eagerly expecting to see new colourful plates of
my favourite birds, however, the artwork throughout the book is largely that of
the Handbook of the Birds of the World, also published by Lynx Edicions. In
retrospect, I fully understand the practical and economic reasons for reusing
the artwork. Regarding the treatment of woodpeckers in this book (and indeed
all other families), although the artwork is from HBW the text and taxonomy are
not. The authors seemed to have been given license by Lynx to divert from HBW
when they wished. For example, Chrysophlegma mentale is not
split into two species here, as it is in HBW. One, perhaps trivial, thing I
must mention is that the suggestion of the name ‘Lilliput Woodpecker’ for Hemicircus
concretus (which HBW calls ‘Red-crested Woodpecker’) when split to
species, was a little jarring.
Although the authors have obviously spent much time
scouring papers, articles and reports, and examined museum specimens, it’s
clear that the solid basis for this fine work is their field experience.
Besides plumages and vocalisations, their acquaintance with behaviour, local
distributions and habitats of the species shines through. Thus, this book is
without question now the indispensable guide for those visiting this bird-rich
region. I shall certainly be referring to it often. All in all, BIRDS OF THE
INDONESIAN ARCHIPELAGO is a user-friendly, practical, well-researched and
professionally produced work, and everyone involved should be congratulated.
Gerard Gorman
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