Today's Guest Author: Miguel D. Saggese, recently back from a conservation trip to Argentina to study Austral Peregrine Falcons.
HEALTH STATUS OF AUSTRAL
PEREGRINE FALCONS (FALCO
PEREGRINUS CASSINI) IN SOUTHERN PATAGONIA, ARGENTINA
Miguel D. Saggese, DVM, MSc., PhD. College of Veterinary
Medicine - Western University of Health Sciences, Pomona, 91767, California msaggese@westernu.edu
Agustin I. Quaglia, Fundación de Historia Natural Félix de Azara. Departamento de Ciencias
Naturales y Antropología. CEBBAD – Universidad Maimonides. Ciudad Autónoma de
Buenos Aires. Argentina
Isabel Caballero, Lic. Cs. Biol, Field Museum of Natural History,
Chicago, Illinois, USA
Dr. David Ellis, PhD., Institute for Raptor Studies, Oracle,
Arizona, USA
Dr. Wayne Nelson, PhD. Institute for Raptor Studies, Oracle,
Arizona, USA
This studied is conducted in collaboration with two other ongoing research projects on this species:
1) Evolutionary genetic structure in a widespread avian predator the Peregrine
Falcon (Falco peregrinus) – PI: Dr. Isabel Caballero and 2) Phylopatry,
breeding success and diet of Austral Peregrine falcons in Southern Argentina – Co-PIs:
Drs. David Ellis and Wayne Nelson (Institute for Raptor Studies, Oracle,
Arizona, USA).
The Austral Peregrine Falcon
The Austral or Patagonian peregrine
falcon (Falco peregrinus cassini) is
one of the less known subspecies of this falcon worldwide. It is found along the Andes Mountains, Patagonian
steppes and sea coasts of southern South America. The current conservation
status of this falcon in Argentina is completely unknown and studies about its health
status are lacking. Many species of raptors, including peregrine falcons, are
globally threaten by human persecution, reduction in the availability of prey,
use of pesticides, collisions with power lines and illegal commerce. Recently,
the roles of macro and microparasites and diseases as an additional cause of
demographic changes in some wild raptors populations, including peregrine
falcons, have been recognized (Newton 2002). As for other aspects of the
Austral peregrine falcon biology and ecology, there is a lack of information
about exposure to macro and microparasites and their potential impact on their
populations. Understanding the role that diseases may play in its decline in
the wild may contribute to its management and conservation. Therefore, during
the months of November and December 2009 we planned to conduct field research
on this species and investigate its health status in southern Patagonia,
Argentina. As veterinarians interested in the role of diseases on wildlife
populations, our specific goals were to 1) establish baseline physiological reference
values (hematology, serum biochemistry and plasmatic cholinesterases) of
free-ranging nestlings’ Austral peregrine falcon; 2) investigate the prevalence
of selected avian infectious and parasitic diseases in these birds, and 3)
train argentine veterinarians, biologists and students in biomedical sampling of
birds of prey.
Why investigate the health status of austral peregrine falcons?
A wide range of macro and
microparasites are known to affect free ranging raptors with variable
consequences, including reduced breeding success and population decline. The prevalence
of bacterial, fungal, viral and parasitic pathogens in free-ranging argentine
raptors has been scarcely investigated and no information exists about the
exposure of austral peregrine falcons to common avian pathogens. A occurs with
other species of birds, including other species of raptors, it is possible that
free-ranging austral peregrine falcons may be exposed to a large list of common
avian pathogens. The list includes- but not limited to- bacteria (Chlamydophila psittaci, Salmonella sp, Campylobacter sp, Mycoplasma
sp., Mycobacterium sp., Pasteurella multocida), viruses (Paramyxovirus 1, Adenovirus, Herpesvirus,
Poxvirus, Influenza virus,
Arboviruses (such as West Nile virus), Fungi (Aspergillus sp.), protozoos (Thricomonas
sp., Plasmodium sp. ),
ectoparasites and gastrointestinal and respiratory parasites as well.
Hematological and clinical biochemistry reference values have
not been reported for austral peregrine falcons. These reference values are
considered useful for monitoring bird’s health status, establish prognosis of
diseases and responses to therapy, assess physiological and pathological
conditions, and evaluate endocrine disruption and immune supression. Pesticide
poisoning (organophosphates, organ chlorines, carbamates and pyrethrins) is
well known for contributing to the death, decreased reproduction and population
declines of several species of birds of prey worldwide. Peregrine falcons
worldwide have been severely affected by the use of organochlorines in the past
century and exposure to these organ chlorines has been previously reported for
austral peregrine falcons by David Ellis in 1986. Peregrine falcons are also particularly susceptible to
the use of organophosphates and strychnine. They are widely used by Patagonian
ranchers as baits to kill foxes, pumas and other carnivores, including birds of
prey.
The field trip
The field trip begun in
Mid-November when David Ellis and Wayne Nelson, raptor biologists that have
studied peregrine falcons in different parts of the world during more than 30
years, conducted surveys for active eyries (nesting sites) of Austral peregrine
falcons. Many of these nest sites were previously surveyed by David Ellis and
collaborators 25 years ago, but haven’t been revisited since then. The main
goals of this survey were to evaluate nest site fidelity, count the number of
active nests and collect samples for population genetic studies. Furthermore, results
of this survey allowed us to access nestlings of this species and collect biomedical
samples so we can investigate their health status. This constituted a certainly
unique opportunity to investigate the prevalence of exposure to selected macro
and microparasites, heavy metals and pesticides that could have a negative
impact on Austral peregrines. In the first days of December, with Isabel
Caballero, we joined David and Wayne in southern Patagonia to focus on the
biomedical sampling of these birds.
Our trip took us to remote
locations in the middle of the Patagonian steppes, where not only we saw
austral peregrine falcons but also we were exposed not only to the rigors of
Patagonia (winds can reach 100 miles per hour and temperature can raise up to 120
F!) but also to its beauties. Breathtaking landscapes and amazing wildlife are
common sightings for the traveler or researcher visiting this remote and wild
area of the world. Guanacos, Culpeo foxes, Maras (Patagonian hares), Choiques
(Darwin’s rheas), Magellanic geese,
Andean Condors and Buzzard Eagles are common inhabitants of the steppe. We were
very lucky by the large number of these and other wildlife species we saw
during our trip. This is an extra benefit that Patagonia gives to the visitors
trying to find its secrets. The white morph of the Austral peregrine falcons is
one of them, no doubt about it. We were lucky enough to investigate several
nesting sites occupied with this little known color morph of this species.
What are the white or pallid austral peregrine falcons?
Austral falcons are the only
subspecies of peregrine falcons worldwide that present a white or pallid color
morph. This color variation was considered a different species for a long time,
since its first description for science in 1920’s. It was originally called
Kleinschmidt’s falcon (Falco kreyemborgii),
until 1980, when David Ellis (USA) and Cesar P. Garat (Argentina) studied the
species in detail and concluded it was just a color morph of the austral
peregrine falcon (Falcon peregrines
cassini). Still, the biology, distribution and conservation status of these
Patagonian white falcons are mostly unknown. We still have so much to learn
about them…
The future
The study started last year
(2009) provided the first ever data available on baseline health parameters and
reference values for the austral peregrine falcons in Argentina and South
America. Combined with additional biological data and population status
obtained simultaneously during this study the expected results will allow us to
better assess the health status of these birds and understand the potential
impact that macro and microparasites and heavy metals may have on free-ranging
populations of Austral Peregrine Falcons in southern Argentina. Furthermore, these
results, together with those from the population status, nest site fidelity,
breeding success and genetic studies, will contribute to a better understanding
of the current conservation status and threats of Austral peregrine falcons in
Argentina and will set the grounds for future monitoring of these populations. In
November and December of 2010 the whole team will head down south again to
visit more nesting sites and continue the work we started at the end of 2009.
All birds underwent a complete
physical examination and blood and other samples were was collected.
NOTE: Information about the exact locations of the different nests will
not be made publicly available to protect the species form human predation, egg
and nestling collection, and other forms of human impact.
Acknowledgements
This project was supported
in part by generous funding provided by The Schubot Exotic Bird Health Center
and Lafeber Company. Special thanks to Dr. LoraKim Joyner for all her support
and encouragement to this project.