Markham's Storm Petrel breeding colonies discovered in Chile

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Markham’s Storm Petrel breeding
colonies discovered in Chile
Fabrice Schmitt, Rodrigo Barros
and Heraldo Norambuena
The Atacama Desert 80 km east of Antofagasta, a huge extension of apparently lifeless sand, rock and salt-plain
(Fabrice Schmitt / WINGS Birding Tours)
Markham’s Oceanodroma markhami (front) and Elliot’s Storm Petrels Oceanites gracilis, off Arica, Chile, October
2009 (Steve N. G. Howell / WINGS Birding Tours)
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The place we are visiting today has not seen
a single drop of rain since humans thought
about monitoring rainfall. We are in the north
of Chile, in the Atacama Desert, the driest place
in the world. Two thousands kilometres of sand,
rocks and salt plains. After a full day’s birding,
we can send our list to eBird: 5 Turkey Vultures
Cathartes aura. at’s it! at is the only species
we have seen today… yet it has been one of our
most exciting trips in the Neotropics!!
Everything began in 2013, when a biologist
from a consultancy company recorded “snipe
singing by night in the desert”. On the recording,
there were obviously no snipe singing, but what
we identified, with the help of Alvaro Jaramillo,
were seabirds. In every Neotropical birder’s mind,
the association of seabirds and Atacama Desert
immediately evokes storm petrel colonies and, for
a few of us, the hope of discovering the Holy Grail:
the first breeding colony of Ringed (Hornby’s)
Storm Petrel Oceanodroma hornbyi!
e Ringed Storm Petrel, as well as Markham’s
O. markhami and Elliot’s Storm Petrels Oceanites
gracilis, are very poorly known species. All three
remain amongst the 62 of the world’s bird species
currently classified as Data Deficient, because too
little is known about them to be able to assign
to them a meaningful threat category (BirdLife
International 2015). Nevertheless, Markham’s
and Elliot’s Storm Petrels are fairly common to
common, and Ringed Storm Petrel uncommon, at
sea off northern Chile and as far north as central
Peru; but almost nothing is known about their
breeding biology. Until 2013, only one breeding
colony of Markham’s Storm Petrel has been found
(Paracas, Peru; 2,305–4,362 pairs in 1992/1993;
Jahncke 1994), a very few nests of Elliot’s Storm
Petrel have been found, all on one island (Isla
Chungungo, Chile; Schlatter & Marin 1983, Hertel
& Torres-Mura 2003), and the location of breeding
colonies of Ringed Storm Petrel is still an absolute
mystery!
In the very first issue of Neotropical Birding,
Tobias et al. (2006) already pointed towards the
Atacama Desert as the likely breeding area for
Markham’s and Ringed Storm Petrels. Every year,
hundreds of flying chicks, still with some down,
are found in the north of Chile—so the breeding
colonies have to be tantalisingly close! But very few
people have spent time in that very inhospitable
area. Mike Brooke is one of them, but even after
spending 25 days on field work in 1999, he failed to
locate any breeding colony (Brooke 2000). During
the last decade, hardly anyone has really looked for
these mysterious birds.
So when seabirds were recorded near
Arica, a group of Chilean birders from the Red
de Observadores de Aves de Chile (ROC, the
Chilean Birding Network), led by Rodrigo Barros,
rapidly decided to organize a first expedition, in
November 2013, with the hope of finding a few
breeding storm petrels. Incredibly, we discovered
multiple evidence of breeding during the very
first day in the field: footprints at the entrances of
cavities, old mummified chicks, several fresh dead
birds (mostly wings), and we even heard chicks
calling deep within the cavities! All the nests were
found in natural cavities in saltpetre crust, at
800–900 m in Pampa de Camarones, 45 km south
of Arica and 10–12 km from the coast. A rapid
estimate made in the field indicates that thousands
of pairs are probably breeding here, only one hour
from Arica!
We later learned that a few months earlier Juan
Torres-Mura and Marina Lemus (2013) had also
discovered a Markham’s Storm Petrel colony 22
km south-east of Arica, in similar habitat (saltpetre
crust). Ironically, after decades of mystery, the
same breeding area had been discovered by two
independent teams almost simultaneously!
But that was just an appetizer! Stimulated
by the discovery of that Markham’s Storm Petrel
colony, we wanted now to prospect the rest of
the Atacama Desert to find more! Since many of
these colonies could be threatened by mining and
other human activities, the Western Alliance for
Nature (WAN Conservancy) rapidly understood
the importance of locating the breeding grounds of
these storm petrels and agreed to cover the costs
of our field work. From April 2014 to April 2015
we carried out six further field trips, comprising
a total of 45 field days, and the detailed results of
these expeditions will be presented in a scientific
journal very soon. Before that, we wanted to share
some of the highlights of our discoveries and
alert conservationists about the threats to these
colonies.
e key question when looking for storm
petrel colonies is: where can they possibly lay their
eggs in such an arid and inhospitable habitat? Eggs
have to be protected from harsh sun, strong wind,
cold nights and—even though there is almost no
life in the desert—from predators such as Turkey
Vulture and Culpeo Lycalopex culpaeus that can
travel long distances to feed on chicks and adult
storm petrels. Breeding in the open would not
seem to be a sensible strategy, even if Grey Gulls
Leucophaeus modestus do so: discovered only
in the early 1940s, their colonies are found deep
within the Atacama Desert (sometimes 100 km
inland), where they lay their eggs in the shade
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>> FEATURE MARKHAM’S STORM PE TREL BREEDING COLONIES IN CHILE

of a large rock, travelling to the colony by night,
perhaps in order to avoid being followed by avian
predators.
We believe that the storm petrels breeding
in the Atacama Desert must dig their burrow
or nest inside a natural cavity, as do the other
storm petrel species of the world. But even if the
Atacama Desert seems to offer almost infinite
opportunities for establishing a colony, most of the
soil is too hard or too soft for a storm petrel to dig
its burrow. e saltpetre crust, on the other hand,
offers wonderful breeding possibilities! e crust
is so hard that few predators can break it to access
the nests, and the holes and space found below
the crust offer a potential breeding habitat for tens
of thousands of storm petrels. After finding our
first colony near Arica, we realised that we had to
focus our search on these salt plains. Actually, this
had already been suggested by Brooke (2000) and,
obvious as the colonies turn out to be, it seems
unbelievable that it took so much time to confirm
his suspicions!
We discovered two main breeding areas in
northern Chile: an extensive salt crust south of
Arica of more than 80 km long and as much as 5
km wide, and the Salar Grande area near Iquique,
potentially 30 km long and 7 km wide. All breeding
colonies have been found between 8 and 20 km
from the coast, at 400–900 m elevation. We do not
yet have enough data to permit a precise estimate
of this breeding population, but we believe that
tens of thousands of pairs are located in northern
Chile. is is probably where most of the world
population of Markham’s Storm Petrel breeds!
During our expeditions, we have been very
concerned by the many threats affecting these
storm petrels. e destruction of their breeding
habitat is pronounced, since the saltpetre crust
beneath which they breed has been intensively
exploited, mostly at the end of the 19th and
beginning of the 20th centuries. In most areas
of the salt plain where the saltpetre crust has
been exploited, there is absolutely no cavity left:
the entire surface has been completely removed,
totally destroying the superficial crust and huge
extensions of potential breeding habitat. e
exploitation of these salts still continues and we
discovered active destruction of breeding habitat
during the breeding season.
e ‘killing lights’ of cities, industries, roads,
and other infrastructure attract the fledglings
during their first flight and have a disastrous
impact too, killing thousands of birds every year.
At the base of one particular light located close to
an active breeding colony, we discovered hundreds
of wings (the bodies are eaten by Turkey Vultures)
and 10–20 fresh corpses every single morning.
Other threats include human construction (a
highway crosses one of the colonies), military
activities (soldiers have been operating and
camping on one colony) and collision with
electrical cables in transit to the breeding sites.
After these first important discoveries,
the ROC is now looking for funding to begin
monitoring the breeding colonies, and to work
with the industries and Chilean government
to control and manage their impact as soon as
possible.
ACKNOWLEDGMENTS
We would like to express our thanks to Rodrigo Silva,
Gail Alfsen, León de Groote, Felipe de Groote, Diego
Davis, Ronny Peredo, Fernando Medrano and Erik
Sandvig for their support in the field. We are grateful
to Steve Howell, Ronny Peredo and Raúl Ignacio Díaz
Vera for authorisation to use their pictures, and to Chris
Wood for permission to use Cornell Lab of Ornithology
data. David Fisher initially suggested I write this article
and Chris Sharpe made corrections and improvements
to successive versions of the manuscript. We also thank
to the Servicio Agrícola y Ganadero for permission
to capture birds for scientific purposes under Exempt
Resolution No. 5022/2014. We are very grateful to Sara
and Larry Wan of Western Alliance for Nature (WAN
Conservancy, www.wanconservancy.org) for funding
our field work; and thanks to Peter Harrison who helped
the WAN Conservancy to raise these funds. And finally
to Vinko Malinarich (SAG Tarapacá) and Fundación
Gaviotín Chico of Mejillones for access to their databases
on storm petrels rescues in the study area.
What about Elliot’s and
Ringed Storm Petrels?
Besides the Markham’s colonies presented here,
we also found hundreds of inactive cavities dug in a
very different geological substrate. In these cavities
we discovered lots of feathers, a few old eggs, and
even a mummied storm petrel chick. The chick’s
DNA is in the process of being analysed to conrm the
identity of the species, although the egg sizes match
the only known egg of Elliot’s Storm Petrel (Schlatter
& Marin 1983). Surprisingly, even after visiting these
cavities at different seasons of the year, we still have
not found any fresh breeding evidence. During our
prospecting we also discovered tens of dead Ringed
Storm Petrels, but nothing to conclusively lead us to
a breeding colony. The Ringed Storm Petrel guards its
secret… and keeps up our levels of excitement during
our eld trips, in the hope that we will discover their
breeding grounds very soon!
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Facing page, top: Landscape at breeding colony, Salar
Grande, south of Iquique, Chile, May 2014 (Rodrigo
Barros / www.redobservadores.cl)
Facing page, bottom: Locations of Markham’s Storm
Petrel Oceanodroma markhami colonies discovered in
2013–2014 (extracted from Cornell Lab of Ornithology’s
Neotropical Birds http://neotropical.birds.cornell.edu
and eBird http://www.ebird.org)
Above, left: Footprints at the entrance of a breeding
cavity, Pampa de Chaca, south of Arica, Chile, April 2014
(Rodrigo Barros / www.redobservadores.cl)
Above, right: Wings of Markham’s Storm Petrel
Oceanodroma markhami found below a “killing light”,
Punta Patache, south of Iquique, Chile, May 2014
(Rodrigo Barros / www.redobservadores.cl)
Right: Markham’s Storm Petrel Oceonodroma
markhami incubating an egg, Pampa de Chaca, south
of Arica, Chile, September 2014 (Ronny Peredo / www.
redobservadores.cl)
Below: A recently edged chick of Markham’s Storm
Petrel Oceanodroma markhami, still with down, Salar de
Pintado, east of Iquique, Chile, April 2014 (Raúl Ignacio
Díaz Vera / www.ickr.com/photos/nacho_dayz)
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REFERENCES
BirdLife International (2015) IUCN Red List for birds.
Downloaded from www.birdlife.org on 09/06/2015.
Brooke, M. De L. (2000) A search for the nesting colonies
of Hornby’s Storm-petrel in the Atacama Desert—
April/May 1999. Ibis 142: 348–349.
Hertel, F. & Torres-Mura, J. C. (2003) Discovery of a
breeding colony of Elliot’s Storm-Petrels (Oceanites
gracilis, Hydrobatidae) in Chile. Orn. Neo. 14:
113–115.
Jahncke, J. (1994) Biología y conservación de la
Golondrina de tempestad negra Oceanodroma
markhami (Salvin 1883) en la Península de Paracas,
Perú. Lima: Asociación Peruana para la Conservación
de la Naturaleza (APECO).
Schlatter, R. P. & Marin, M. A. (1983) Breeding of Elliot’s
Storm Petrel Oceanites gracilis, in Chile. Le Gerfaut
73: 197–199.
Tobias, J. A., Butchart, S. H. M. & Collar, N. J. (2006)
Lost and found: a gap analysis for the Neotropical
avifauna. Neotrop. Birding 1: 3–22.
Torres-Mura, J. C. & Lemus, M. L. (2013) Breeding of
Markham’s Storm-Petrel (Oceanodroma markhami,
Aves: Hydrobatidae) in the desert of northern Chile.
Rev. Chilena Hist. Nat. 86: 497–499.
FABRICE SCHMITT
E-mail: fabrschmitt@yahoo.com.ar
RODRIGO BARROS
E-mail: barrilo@gmail.com
HERALDO NORAMBUENA
E-mail: buteonis@gmail.com
Landscape at breeding colony, Salar Grande, south of Iquique, Chile, May 2014 (Rodrigo Barros / www.
redobservadores.cl)
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