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Introduction
● The american Black vulture or Coragyps atratus is native raptor to the americas.
● Range is generally stretches from south america to lower united states● Solid black body, though white spots are common. The bare skin of its
head is also black. ● Wing span from 137-150 cm. Body size can range between 60-68 cm.
Its weight as an adult can range from 1600g -2200g.
Life history/Ecology
● Habitat: generally found in woodland habitats. May roost in sites that are close to water.
● Reproductive behavior: lays about 1-3 eggs in dark crevices. They are monogamous and can stay with one partner for many years. Hatchlings are cared for generally 8 months until hatchling is old enough to be on its own.
● Migration: Very small numbers wander to Cuba, presumably from the continental USA, mainly in winter.
Population status and distribution
● Abundance: There are approximately 20 million birds in its range. Population increased between 1966 to 2014.
● Survival: Black vultures tend to live into their twenties. ● Carrying capacity: Not known● IUCN declared “least concern” species; Not vulnerable to extinction
○ Vital rates suggest an increasing intrinsic growth rate.
Threats/reasons for management
● There is no potential threat to the species.○ Species are viewed as a pest. Causes major damage on
infrastructure as well as be considered noise nuisances. ○ There is no worry of over harvesting. They are growing above
stable growth rate.● The main consequence of overpopulation is financial increases in
property damage. Also an increase in property damage in itself.● Main issues for NJ are property damage and noise nuisance.
Current conservation/ Management efforts
● Regulatory protection: Migratory Bird Act● Habitat conservation and restoration:
○ Considered a nuisance species. Habitats are mostly along highways, on roofs, and near farms.
● Restrictions, licenses: Migratory Bird Act. ○ The birds, their nests, and eggs cannot be killed or destroyed
without a Migratory Bird Depredation Permit.
Current conservation/ Management efforts (Cont.)
● Public outreach? Education? ○ WS State offices may be consulted for more specific local information. WS provides advice and
direct management to help people resolve vulture conflicts. Vulture management is
complicated and site-specific, so consultation with wildlife professionals is vital to successfully resolving damage situations.
● What strategies are working? Aren’t working? In NJ?○ Roosting vultures have been effectively hazed with red lasers. Effigies of vultures suspended
from a line (upside down) have been reported to be quite effective at dispersing roosts. Audio
hazing has not been found to be effective. Shooting-Effective, if proper permits obtained. Trapping: Not practical, and permits required.
Conservation/ Management Plan
● Recovery objective: lower the survival rate of subadults and adults. Management plan implemented over 4-5 years
● Population of 15000 considered stable and healthy.
● Success will be assumed when overall index of species have decreased among sites in NJ. Also a survey looking at the overall damages and viewing decreases in damage costs.
Conservation/ Management Plan Continued...
● Conservation/ Management strategy○ Control survivorship of vultures by killing
■ Continue existing shooting regulations that manage black vulture■ Allow hunting of the vulture in common habitats■ Hire hunters
● Engage public○ Pamphlets and conservation information to provide to locals○ Communication to local and state officials○ Seminars and conservation talks
Conservation/ Management Plan Continued...
● Stochastic population model○ Sensitivity and elasticity analysis.
■ Focus on subadult and adult survivorship● Cannot discern between the two
● Long term goal Implementation○ Population will eventually exceed stable growth rate
■ Decrease initial growth rate lower than 1 (0.9%)■ Stabilize the growth rate by relieving harvest stress on species■ Continue current Black Vulture management
Conservation Models explained
F(h) F(j) F(sa) F(a)
Eggs: 0 0 0.4987 0.4987
Juveniles 0.875 0 0 0
Subadults: 0 0.8905 0.657 0
Adults: 0 0 0.249 0.906
Elasticity matrixF(e) F(j) F(sa) F(a)
Eggs 0 0 0.10789871990.0809368886
2Juveniles 0.2182708061 0 0 0Subadults 0 0.1819029659 0.1568703163 0
Adults 0 00.0779654865
40.1761548167
Conservation Models explained
F(e) F(j) F(sa) F(a)
Eggs: 0 0 0.4987 0.4987
Juveniles 0.875 0 0 0
Subadults: 0 0.8905 0.251 0
Adults: 0 0 0.249 0.5
Elasticity matrixF(e) F(j) F(sa) F(a)
Eggs 0 0 0.08411489989 0.07549005418
juveniles 0.1596049541 0 0 0
Subadults 0 0.1596049541 0.1991846008 0
Adults 0 0 0.07549005418 0.2465104828
Conservation models explained
F(e) F(j) F(sa) F(a)Eggs 0 0 0.4987 0.4987
Juveniles 0.875 0 0 0Subadults: 0 0.8905 0.371 0
Adults: 0 0 0.249 0.62
Elasticity matrixF(e) F(j) F(sa) F(a)
Eggs 0 0 0.11765375340.0761238577
2Juveniles 0.2411698223 0 0 0Subadults 0 0.2164086904 0.126667865 0
Adults 0 00.0850142813
50.1369617298
Future Prospects and Research...
● Still need reliable vital rate data● More information concerning survivorship can lead to better
management plans● Green roofs as alternative● Better methods of public engagement