[Il Falco Del Nord Download Full Movie Free
Abdul Soumphonphakdy
Largest falcon. Heavily built. Grey upperparts and white, speckled underparts. Juveniles with browner plumage than adults, blue-grey legs and longitudinal streaking below. Diffuse moustache-stripe, and the whole head seems dark at distance, lacking a defined cap. Rounder and broader wings, longer tail and bulky belly distinguishes it from Peregrine. Underside of wings with dark coverts in contrast to pale base of flight-feathers. Extremely powerful, but slower flight action than Peregrine.
A coarse, drawn out, Peregrine-like "kaaawt", with emphasis on ending, is repeated in series. Much slower paced than in small falcons, and deeper and with different attack than in Peregrine. Also shorter, coarse warning-calls.
Large and athletic falcon. Adults slate-grey above. Underparts white with black barring. Head almost black. Juveniles with brown tone to plumage, coarse longitudinal streaking below and paler head. Differs from the smaller falcons by less pointed wings, heavier hips and short tail. Highly contrasting and broad moustache-stripe. Smaller than Gyrfalcon with a more compact silhouette. The wings are not as broad, and belly not as deep. Underside of wings evenly barred, without contrasting coverts. Flight-pattern can recall Fulmar, with shallow, stiff wing-action.
The Northern Aplomado Falcon wasmost commonly observed and collectedin its U.S. range during theperiod 1870-1930. The falcon seeminglydisappeared in the U.S. afterthe 1930s for reasons that largelyremain a mystery. It is noteworthyto consider that the Aplomado Falconwas at the northern limits of its continentalrange in southeastern Arizona,southern New Mexico, andwestern and southern Texas; and,therefore, possibly vulnerable tosmall changes in habitat quality inthis region.
Severe overgrazing by domesticlivestock and resultant brushencroachment in the Southwest,including Texas, has been most frequentlyimplicated as the principalcause for the species' decline. Directadverse effects of livestock grazing onpotential falcon prey species havealso been suggested as a possiblecause. However, a recent review ofthe history of livestock trends andpractices and other ecological factorsin the Southwest in relation to thedecline of Aplomados suggests differentcauses.
In the late-1800s, large numbersof cattle were introduced onto Southwestgrasslands occupied by Aplomadosand their numbers remained highthrough the 1920s. Decades of overstockinghad degraded desert grasslandsby the 1920s. Recognition ofthis led to reductions in cattle numbersby the late-1920s and 1930s, particularlyafter passage of the TaylorGrazing Act in 1934. However, cattlestocking rates may have remainedcomparatively high in western andsouthern Texas well into the late-1900s, since these ranges were mostlyin private ownership and not subjectto regulation by the federal act. Atleast at some Arizona and New Mexicosites where Aplomados occurred,brush did not extensively invade intograsslands until after the 1940s
There is some evidence fromearly naturalists to support thenotion that prairie dogs greatlyexpanded in the Southwest after theintroduction of large cattle herds.Widespread and intensive grazing bycattle may have stimulated such anexpansion, since prairie dogs requirelow-stature grassland habitats.Regardless of the cause, prairie dognumbers and acreages occupied wereextremely high during the late-1800sthrough about 1920. A U.S. governmentcampaign to control prairiedogs on publicly-owned lands in Arizonaand New Mexico by use ofstrychnine poison began in 1912, anda similar state effort was initiated inTexas in 1915. Prairie dogs weresubstantially reduced through poisoningby the 1920s, their declinepeaked in the 1930s, and they werevirtually eliminated from southeasternArizona and southwestern NewMexico by the 1940s and 1950s,respectively. This pattern of declinewas probably mirrored in westernTexas, except that prairie dogs werenever completely eradicated and somepopulations have persisted therethrough the present time.
Historic ranges of the blacktailedprairie dog and the NorthernAplomado Falcon in the Southwest, toinclude western Texas (prairie dogsnever occurred during historic timein southern Texas), matched closely.This has led to speculation that habitatconditions generated by prairiedogs may have benefited AplomadoFalcons. It is reasoned that overallabundance, biomass, and catchabilityof avian and small mammal preywere greater inside prairie dog townsthan in the surrounding grasslands.At least some potentially importantavian prey species, such as meadowlarks,some plovers, MourningDove, Horned Lark, and others, seemto respond positively to grazing.Others, like the Borrowing Owl, aredirectly dependent on prairie dogborrows and other prairie dog habitatfeatures for optimal nesting and rearingof young. Insects, reptiles, birds,and small mammals that used prairiedog colonies were probably easier todetect and catch by Aplomados thanin surrounding grasslands, whereherbaceous vegetation was denserand higher. In similar ways, cattlegrazing may have provided short-termbenefits to Aplomados.
The natural coincidence ofAplomado and prairie dog distributionsin the Southwest (outside southernTexas) and their simultaneousdeclines suggest that these eventsmay have been related. Prairie dogswere eradicated by strychnine poisoning.This method of control was nonselectiveand undoubtedly killedother wildlife in the vicinity of dogtowns. Aplomado Falcons could havebeen adversely affected by feeding onpoisoned birds and mammals throughrelay toxicity. Relay toxicity alsocould have killed other raptors andravens that provided nest platformsfor Aplomados.
It appears that a majority ofhistoric encounters with AplomadoFalcons and high numbers andacreage of black-tailed prairie dogscoincided with historically high livestockstocking rates on Southwestgrasslands (all between 1870 and1920). Aplomado falcons and blacktailedprairie dogs, with overlappingdistributions, disappeared from theSouthwest landscape in the 1930s.Although, it is clear that prairie dogswere intentionally eradicated, causesof the Aplomados disappearanceremain obscure. In Arizona and NewMexico, large scale mesquite andother shrub invasion into grasslandsappears to have occurred after thedemise of the falcon.
Other factors could have affectedthe decline. Aplomado Falcons disappearedrapidly throughout their U.S.range, which suggest that a widespreadphenomenon such as climatechange could have been involved.Throughout the U.S. and Mexicanrange of the Northern Aplomado Falcon,the long-term, cumulative impactof cattle grazing to the recovery ofthis subspecies probably has beennegative, since it eventually contributedto the evident degradation ofdesert and coastal grasslands. Grazingby cattle increases the spread ofmesquite, diminishes water retentionon rangelands through soil compactionand loss of herbaceous plantcover, and interrupts natural fireregimes by reducing plant fuel loads.In southern Texas, relatively highnumbers of falcon eggs and specimenswere collected by professionalcollectors during the early-1900s andpossibly contributed to the disappearanceof Aplomados in that region.Particularly in southern Texas andeastern Mexico, but also portions ofthe Aplomado's former desert range,large tracts of native grassland havebeen converted to pasturelands andcroplands, thereby further reducingthe extent and quality of AplomadoFalcon habitat.
The pesticides DDT and DDEwere not factors in the Alpomado'sdisappearance, since they were notintroduced into the environmentuntil the late-1940s. Even thoughthese pesticides have been banned inthe U.S. for over 30 years, heavy concentrationsof DDT and DDE persistsin potential prey species in the U.S.and northern Mexico. Furthermore,these pesticides are still in use inMexico and other parts of LatinAmerica. In eastern Mexico, DDT andDDE contamination has led to severeeggshell thinning in Aplomados.Birds and other organisms collectedover the past decade from the lowerRio Grande, Laguna Madre, and othersouthern Texas locations containedheavy loads of PBCs, heavy metals,and organochlorine pesticides.Organophosphate pesticides are stillheavily used throughout the range ofthe Aplomado Falcon, including in theU.S., and remain a serious threat toAplomados. This group of pesticideshas been linked directly to the deathsof thousands of songbirds, waterfowl,and raptors in Argentina and parts ofthe U.S. Other threats include directloss of habitat from various forms ofhuman development, secondary leadpoisoning through ingestion of gamebirds (doves and quail), electrocutionby improperly designed electricaltransmission lines, and human disturbancein breeding areas.
In 1986, the Northern AplomadoFalcon was federally listed as endangeredin the U.S. and Mexico basedon evidence of population declines inthe U.S. and threats to reproductionin eastern Mexico related to pesticidecontamination. Subsequently, thenorthern subspecies was state-listedas endangered in Arizona, NewMexico, and Texas, and in 1990 afederal recovery plan was prepared.
In the years since listingoccurred, general awareness of theAplomado's peril has grown, surveillanceof the falcon has increased, considerationof and planning forAplomado habitat requirements onpublic lands has improved; and newresearch, focused on the Aplomado'spopulation ecology and habitat preferencesand requirements, has beeninitiated. In 1992, two small, isolatedpopulations of Aplomados werediscovered in north-central Chihuahua,Mexico in close proximity tothe U.S. Ongoing monitoring andresearch efforts at these sites are providingimportant insights into thedesert grassland ecology of thisspecies. Recently, another researchmanagementeffort led by U.S. departmentsof Interior and Defensecharacterized occupied AplomadoFalcon habitat in northern Mexicoand then used that habitat "footprint"to identify potentially suitable falconhabitat in the U.S. The TurnerEndangered Species Fund alsorecently funded a historical review ofland use and ecological conditionsthat surrounded the Aplomado in theSouthwest at the time of its decline.
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