Grey Duiker

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Grey Duiker

• Site One

• Site Two

• 11.76 of trays unforaged during silent
  treatments
• 29.41 of trays unforaged during playbacks

• 5.88 of trays unforaged during silent treatments
• 23.53 of trays unforaged during playbacks

2
Eagle alarm
Leopard alarm
Snake alarm
3
Greater Bush Baby
4
Relevance?
So other than being really coolare these
behaviors relevant? Are they trait-mediated
interactions? And what kind?
From the preys perspective they are
facilitators they reduce the negative effect
of hawks ( effect on chipmunks)
From the hawks perspective they are a
pain-in-the-ass a sort of Heterospecific
Vigilance
5
Actually titmice are what we might call KEYSTONE
SIGNALLERS
They are the core members of mixed winter flocks
of birds Nuthatches have reduced survival when
titmice are removed!!
They (Blue tit in the Netherlands) facilitate
settlement of breeding passerines
They facilitate movement through fragmented
landscapes, following passerines are more likely
to move through dangerous matrix when they
accompany titmice

• The removal of Titmice from the environment may
  result in the loss(??)
• or reduction in abundance of numerous other
  passerines and even small
• mammals

6
Behavioral Landscape Ecology
Is landscape connectivity influenced by the
presence of vocal cues of predation risk? Are
parids Keystone signalers?
300m
S
S
S
A
A
A
S
Alarm call
A
Song
S
A
A
A
S
S
S
S
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Cossypha robin-chats mimic the alarm calls of
other species and intersperse them with their
own alarm calls when young are at risk.
Interpretation Increased alarm literacy via
learning by association .
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Eavesdropping in a Caching-Pilfering system
CACHE-ROBBER
INFO
Signaler
Receiver (intended)
(sender)
(recipient)
CACHER
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How should squirrels change their behavior in the
perceived presence of a cache robber?

• - False-caches
• - Cache less often
• Cache in remote/hidden locations
• Frequent recaching

Reduce the Future Value of food
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Hypotheses
? Squirrels eavesdrop on blue jay vocalizations
? Squirrels perceived jays as prospective cache
robbers
Predictions

• Squirrels devalue cacheable food in the
  perceived presence
• of jays (i.e., reduce the future value of
  cacheable food)
• ? Squirrels will devalue cacheable food when jays
  are near but
• not at sites where jays are distant

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Food spoils and ripens.hence, a food that
stores well has higher future value
Cacheable Nuts Future Value (cached 54 of 55)
Non-cacheable Nuts No Future Value (ate 52 of 55)
Kotler et al. 1999
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Detecting changes in Future Value
P predation cost MOC missed opportunity
cost C metabolic cost QHR quitting harvest
rate ?F/?e marginal value of energy
QHR P MOC C
will result in ? QHR or ? GUD
?
Compare GUDs on cacheable food With and Without
the perceived presence of jays while holding GUD
on non-cacheable food fixed (i.e., compared to a
fixed currency)
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Speaker (jay or winter birds)
station of two trays
100m
25m
75m
Cachable food hazelnuts in the shell
Non-cachable food hazelnuts with shell removed
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100m
25m
75m
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Results
9
7
GUD (number of nuts remaining)
5
3
Control
Away
Near
Blue jay

• Squirrels devalue cacheable food in the
  perceived presence of jays

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Moving on
Whats in the mind of a squirrel??