35_Conservation - School of Life Sciences

advertisement
Announcements
This week:
Wednesday - Review
Friday - Exam 3 (here and in 100 Greg Hall)
Next week:
Monday and Wednesday - Human Sociobiology
Final Exam - Friday, May 11, 8 am
What is Conservation Biology?
“The Science of Scarcity and Diversity”
Soule 1986
What is Conservation Biology?
“A new synthesis of many basic sciences that provides
principles and new approaches for the applied fields of
resource management”.
Temple 1991
What is Conservation Biology?
“A multidisciplinary science that has developed to deal
with the crisis confronting biological diversity. Goals: to
investigate human impacts on biological diversity, and to
develop practical approaches to prevent the extinction of
species.”
Primack 1993
What is Conservation Biology?
“An integrative science pertaining to the preservation of
species, ecosystems, and their diversity.”
Books and Edited Volumes
Caro , T. (ed.). 1998. Behavioral Ecology and Conservation Biology. Oxford
University Press, New York, New York.
Clemmons, J.R., and R. Buchholz (eds.). 1997. Behavioral Approaches to
Conservation in the Wild. Cambridge University Press, New York, New
York.
Festa-Bianchet , M. and M. Apollonio (eds.) 2003. Animal Behavior and
Wildlife Conservation. Island Press, Washington, D.C.
Gosling, L.M., and W.J. Sutherland (eds.). 2000. Behaviour and
Conservation. Cambridge University Press, New York, New York.
Sutherland, W.J. 1996. From Individual Behaviour to Population Ecology.
Oxford Series in Ecology and Evolution. Oxford University Press, New
York, New York.
Issues in Conservation Biology that can benefit
from the study of Animal Behavior:
Captive Breeding and Reintroduction
Species Management Plans
Habitat Loss and Fragmentation
Biological Invasions
Captive Breeding and Reintroduction Programs
Captive Breeding
Need to know requirements for breeding
Social structure
Komodo Dragon
Published online 21 December 2006
Parthenogenesis in Komodo dragons
Phillip C. Watts, Kevin R. Buley, Stephanie Sanderso, Wayne Boardman, Claudio Ciofi and
Richard Gibson
Should males and females be kept together to avoid triggering virgin
birth in these endangered reptiles?
Parthenogenesis, the production of offspring without fertilization by a male, is rare in
vertebrate species, which usually reproduce after fusion of male and female gametes. Here
we use genetic fingerprinting to identify parthenogenetic offspring produced by two female
Komodo dragons ( Varanus komodoensis ) that had been kept at separate institutions and
isolated from males; one of these females subsequently produced additional offspring
sexually. This reproductive plasticity indicates that female Komodo dragons may switch
between asexual and sexual reproduction, depending on the availability of a mate — a
finding that has implications for the breeding of this threatened species in captivity. Most
zoos keep only females, with males being moved between zoos for mating, but perhaps they
should be kept together to avoid triggering parthenogenesis and thereby decreasing genetic
diversity.
Captive Breeding and Reintroduction Programs
Reintroductions
Many reintroduction attempts fail because captive bred
animals lack “skills” needed to survive.
recognize and respond to predators
locate food and water
distinguish toxic from palatable food
recognize conspecifics as mates
interspecific recognition
predator / prey interactions
host / parasite interactions
naïve prey responding to cues of introduced predators
learned response
innate response
New Zealand Robin
and mustellids
Rana aurora
bullfrogs and crayfish
Maloney & McLean
1995
Pearl et al. 2003
California condor
Imprinting on humans affected the ability of animals
reintroduced in the wild to associate with other condors and
breed.
Species management and viability
A. Population size (N) versus Effective Population size (Ne)
Female deaths reduce Ne
Monogamous species N = Ne
parental care requires both parents to be present
hard to find mates at low population sizes
Polygynous species N >> Ne
killing of dominant males leads to mating of “less fit males”
choosy females don’t mate?
Species Management and viability
B. Specific habitat or nesting requirements
mating systems
leks
cavities and old growth forests
Essen (1991)
Attempted to change nesting locations and migratory
routes lesser white fronted goose to help conserve
threatened population in Sweden
whooping crane
sand hill crane
“The cheetah controversy”
1983 Steve O’Brian and colleagues
Cheetah has very low genetic diversity
- suffer high juvenile mortality
- impaired reproduction (low sperm viability)
- increased susceptibility to disease
“The cheetah controversy”
1994 Caugley and Merola
Low genetic diversity, big deal
- lots of carnivores have low levels of diversity and
low sperm viability.
- No direct link between lack of diversity and
juvenile mortality
“The cheetah controversy”
1994 Caro and Laurenson
Long term behavioral studies showed
that cub mortality result of predation by
lions and hyenas while mother was out
foraging.
“The cheetah controversy”
1998 Kevin Crooks and colleagues
Using demographic data, examined which life stage makes
cheetah populations most vulnerable to decline
Cheetahs go into estrus immediately after cubs die
Small increases in adult mortality have greater effect on
population than cub mortality.
Under old law, no dolphins are to be encircled by tuna purse
seine nets in order to be able to claim a dolphin safe label.
New US government label would mean that such nets can be
set on dolphins, but that "no serious injury or mortality" of
dolphins can be observed.
Consequences of hunting on species’ biology
Hunters also use sexually selected traits to assess value…
Number of mates / longevity
expected…
Horn size
Undesirable evolutionary consequences of trophy hunting
Coltman et al. 2003 Nature.
1970
Undesirable evolutionary consequences of trophy hunting
Coltman et al. 2003. Nature.
2005
Habitat Loss and Fragmentation
Dispersal
Corridor Use
Edge Effects
Home Range Size
Influenced by:
Social Structure
abundance and density
Mating Systems
area and resource requirements
Habitat Loss and Fragmentation
Dispersal
Corridor Use
Edge Effects
Home Range Size
Home range size can determine which / how many
species persist in a fragmented landscape.
Crooks 2002 Con. Biol.
Biological Invasions
Introduced (non-native, exotic)
- species introduced deliberately or accidentally from
somewhere else
Invasive species
- species that spread subsequent to establishment
usually at some cost.
Biological Invasions
Competitive displacement of native species
behavioral mechanisms of success
Determining patterns and rate of spread
dispersal (natural versus human mediated)
“hyperconnectivity”
Establishment Success
sociality and allee effects
Download