The first time that they talked about the evidence of a two seasonally breading populations of Oceanodroma storm-petrel in the Azores Islands was in 1996. Recent mtDNA and microsatellite analysis from storm-petrel populations has considerably advanced the understanding of their taxonomic relationships.
The investigators concluded that the hot-season Azores population should be considered a new specie. The species is both genetically distinct and genetically isolated from the cool-season population of Madeira Storm-petrel Oceanodroma castro.
The name suggested for this species is Monteiro strom-petrel Oceanodroma monteiroi.
Differences in the vocalizations permit species recognition, and the extent of primary feather wear and stage of moult aids to the separation of this specie, especially in during August. Monteiro's Storm-petrel is thought to be confined to the Azores archipelago, where it is currently known to nest on just two small neighboring islets. The total population size was estimated at 250–300 pairs in 1999.
For more detail, please consult:
Monteiro's Storm-petrel Oceanodroma monteiroi: a new species from the Azores. MARK BOLTON, ANDREA L. SMITH, ELENA GÓMEZ-DÍAZ, VICKI L. FRIESEN, RENATA MEDEIROS, JOËL BRIED, JOSE L. ROSCALES & ROBERT W. FURNESS
sexta-feira, 14 de novembro de 2008
terça-feira, 28 de outubro de 2008
Can birds smell a predator at distance?
The presence of a chemosensory system able to detect food and predators is very common among living organisms, especially in aquatic environments.
This olfactory abilities can be quite complex in some organism, like for example, the fathead minnows, Pimephales promelas, that can detect the number, size proximity of their predator by chemical cues alone. Others can use olfaction to assess their predators diet, thereby determining the threat posed by a given predator.
There is a certain common assumption that birds have a very weak scent of smell. There are a few exceptions. Tubesnoses may use their smell to detect decaying fish and plankton from kilometers away and Kiwis use it to locate their food on soil and mud.
Along evolution bird retain the anatomical and neurological structures for detecting olfactory cues and so use olfaction in some extent. Size and complexity of the olfactory bulb varies across taxa, and this variation is likely to be adaptive.
Passerines are those that are considered to have the smallest olfactive bulb. In a way to demystify this, some scientists investigated the ability of a bird to scent a predator.
They used houses finches and exposed them to a feeder/scent delivery mechanism. During the feeding time, birds were exposed to 3 different smells: cat fecal cues, rabbit fecal cues and water. The birds were unable to see the content of the stimulus cups.
After watching the records, they noted that house finches delayed the feeding time, spend less time on the feeding platform and reduced their vigilance on the different stimuli. Birds strongly responded to cat faeces. Scientist noted that the behavior of the bird was different on the presence of the mammal cues, and a normal behavior was kept when water was the cue.
This simple experience is an evidence that birds can detect mammals cue while foraging. This type of studies, on animal behavior, became important to understand certain ecological mechanisms. Understanding the nature is also taking part of their conservation.
This olfactory abilities can be quite complex in some organism, like for example, the fathead minnows, Pimephales promelas, that can detect the number, size proximity of their predator by chemical cues alone. Others can use olfaction to assess their predators diet, thereby determining the threat posed by a given predator.
There is a certain common assumption that birds have a very weak scent of smell. There are a few exceptions. Tubesnoses may use their smell to detect decaying fish and plankton from kilometers away and Kiwis use it to locate their food on soil and mud.
Along evolution bird retain the anatomical and neurological structures for detecting olfactory cues and so use olfaction in some extent. Size and complexity of the olfactory bulb varies across taxa, and this variation is likely to be adaptive.
Passerines are those that are considered to have the smallest olfactive bulb. In a way to demystify this, some scientists investigated the ability of a bird to scent a predator.
They used houses finches and exposed them to a feeder/scent delivery mechanism. During the feeding time, birds were exposed to 3 different smells: cat fecal cues, rabbit fecal cues and water. The birds were unable to see the content of the stimulus cups.
After watching the records, they noted that house finches delayed the feeding time, spend less time on the feeding platform and reduced their vigilance on the different stimuli. Birds strongly responded to cat faeces. Scientist noted that the behavior of the bird was different on the presence of the mammal cues, and a normal behavior was kept when water was the cue.
This simple experience is an evidence that birds can detect mammals cue while foraging. This type of studies, on animal behavior, became important to understand certain ecological mechanisms. Understanding the nature is also taking part of their conservation.
Author: Sónia Manso
sábado, 11 de outubro de 2008
Quinta do Lago guided tours
We offer you an half day guided tours in Quinta do Lago, visiting the Lake and the salt marshes on foot. Bring curiosity, you offer you spots and information about birds and local habitat.
Know more about our Nature Walks
Know more about our Nature Walks
Birdwatching on a boat tour
Visit the Ria Formosa salt marshes and observe a enormous variety of wading birds. The electric motor of the vessel allow us nice approaches guaranteeing the minimumj impact on the wild life.
More information about bird watching boat tour in the Algarve - Portugal.
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