Usgs Bird Population

UsgsBird Population

UsgsBird Population

Classificationof species within the generalist/specialist gradient or literaryseparation of families with broad environmental niche from those withnarrow functions is not only a practical but contentious topic in thetheoretical world (Devictor, 2012). The theory of ecology assertsthat the niche-based differences are due to the evolutionaryprocesses between the capability of organisms to exploit the scarceavailable resources and their ability to make use of them. This paperprovides a platform to focus on this concept using specific species.I will concentrate on the generalist and specialist birds beforenarrowing to Hooded Merganser, Great Blue Herron, Wood Stork, and theAmerican Robin as the selected classes.

Generalistvs. Specialist birds

Livingorganisms typically exist on a scale having generalists on one sideand the specialist on the other end. Specialists have particularhabitats in which they can survive. They can only thrive in a narrowvariety of surroundings with a certain climate, diet, and otherprecipitating factors. On the other side, generalists have theability to live in a wide range of conditions and changes within theecological setup (Devictor, 2012). Studies have shown thatspecialists can only survive when conditions are conducive. They aregood at competing with other organisms and can easily cope up withthe common risks. However, in the case of changes, they becomeextinct. Generalists will radically response to any unanticipatedalterations and continue surviving for extended periods of time sincethey can feed on any food, live in numerous climates, and use simpletechniques for defense.


Itis one of the two Storks that exist in North America. The bird islarge with long legs and exists in marshy, cypress, and mangroveswamps. Its breeding is situated concentrated in the South-Easternpart of the United States of America in all the coastal states whereit lives in colonies with egrets, ibises, and other species.

Woodstork falls within the specialist bracket of birds (Devictor, 2012).It has a unique feeding technique suitable for feeding in waterregions. They entirely feed on fish making the freshwater habitatappropriate for its nesting, staying and hunting.

GreatBlue Heron

Thisis the biggest wading bird within North America. They exist in threedifferent regions. The parts range from Florida to the Pacific coastof Canada. Though they primarily feed on fish, they are a generalist(Devictor, 2012). They hunt their prey by walking or standing inshallow waters along the coastal line and vegetative regions. Theyalso feed on small mammals and amphibians.


Thebird is in a generalist bracket. In their range, they exist in almostevery forested and woodland region. In Alaska, they mainly live inspruce forests in lower areas and alpine willow thickets (Devictor,2012). They feed on earthworms, creepy-crawlies, and snails. Berriesalso heavily supplement their diet. During winter they fly south toBermuda and Guatemala while in summer they are found throughout NorthAmerica.


Hoodedmerganser is a generalist. It exists in a wide range of habitat fromwoodlands, forests, and aquatic regions (Devictor, 2012). It feeds onfish, mollusks, crustaceans, insects and frogs. It also survives onaquatic vegetation and grains. Its distribution is wide along thecoastal line and the southern parts of the interior. Nonetheless, inthe northern region, the distribution is scattered.


Itis clear that each species has a particular environment andcharacteristics for survival from the discussion. Unfortunately, theecological changes in the modern world are likely to alter thesituation and even endanger some of the species.


Devictor,V. (2012). Distribution of specialist and generalist species alongspatial gradients of habitat disturbance and fragmentation. Oikos,117(4),507-514.