Isabela eps:Layout 1 - Advanced Conservation Strategies

RESULTS & EFFORT
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Santiago: Judas phase
Judas goats strategy outcomes
FACT BOX
Helicopter facts
• 13,390 km flown of which:
- 2%(2004), 97%(2005), 1%(2006)
• 9.6 days non-stop equivalent
Ground facts
• August 2004 to July 2005
• 14 trips
General facts
• 913 Judas released on checks
• 284 Captured & translocated
Judas goats on Santiago
Judas goats were monitored by ground and aerial
hunting crews on Santiago about 1,400 times.
Ground hunters invested 5,010 hours and dogs
7,720 hours, while 231 helicopter hours were
flown. Kills in this phase accounted for 1% of all
goats killed on Santiago. Some 617 goats were
killed associated with Judas goats; 319 and 298
were killed by aerial and ground checks respectively.
A further 557 goats were killed unassociated with
Judas goats; 97 and 460 were killed by aerial and
ground checks respectively. On average, ground
hunter checks were nine times more expensive than
helicopter checks. However, as dogs detected more
goats that were not associated with Judas goats, the
final costs per goat killed during this phase were
almost identical for helicopter and ground crews.
Group sizes of goats killed during the Judas goat
phase on Santiago. Purple dots indicate feral goats
killed that were not associated with Judas goats. Pink
dots are feral goats that were shot while associated
with Judas goats.
Ideal helicopter country
Isabela: aerial hunting phase
FACT BOX
Hunting results
On Isabela, helicopter crews removed 98% of all goats; the terrain and vegetation was, in general, ideal for aerial hunting.
Goats were shot on all volcanoes, with the highest densities occurring on Alcedo, Darwin and Wolf. Aerial hunting was
extremely efficient and allowed areas to be covered that would have been near impossible to cover by foot. One area
proved difficult to hunt from the air. Dense vegetation on the southern slopes of Alcedo was hunted intensively but many
animals still remained. Goats altered their behavior, becoming motionless and hiding under vegetation where they were
generally safe from detection by aerial crews. Methods were switched after aerial hunting had removed all the animals
possible (read further p.30).
Period: May, June & December 2004 + January
to March 2005
• 56,657 goats eradicated
• 98% of total goats eradicated
• 46,664 in 2004 & 9,993 in 2005
• 54% eradicated 0-500 m. alt.
• 33% eradicated 500-1000 m. alt.
• 13% eradicated > 1000 m. alt. & inside craters
* Unlike on Santiago Island, no black goats were seen
on Isabela Island
Hunting km flown
• 72.761 km total (1.8 times the earth’s circumference)
• 43,957 km in 2004
• 27,533 km in 2005
• 1,271 km in 2006
Hunting hrs flown
• 1,258 hrs total (52.4 days non-stop)
• 930 hrs in 2004
• 312 hrs in 2005
• 16 hrs in 2006
Tracking on down Isabela
With Santiago’s recent experience fresh in their
minds, the helicopter crews were well prepared
when they arrived on Isabela. After a general
orientation flight aimed at identifying some of the
goat’s living areas, the hunting phase was
launched. A whole month based on volcano Wolf
enabled them to work the northern part of Isabela
thoroughly, flying more and spending more time
than originally planned due to the unexpected
high number of goats.
After being based at a temporary camp
on northern Isabela, the group then
moved to the permanent camp where
they were based until the end of March
2006; Cowley base in Alfaro Point, on
the eastern side of Isabela. From there,
work was targeted on Alcedo and
Darwin. Alcedo stands out as the
problematic volcano as it had the
largest goat population. Hunting flying
time and kilometers flown are on a
different magnitude than any previous
job! The flying tracks on the map show
how all of Alcedo area is suitable for
goats, as opposed to any other volcano
where more lava areas restrict the
populations into the smaller reduced
vegetated regions.
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RESULTS & EFFORT