Transcript Habitat Considerations for Endangered Species

Habitat Considerations for
Endangered Species
 Why conserve habitat?
 Sinks, sources, and metapopulations
 Critical Habitat
 Habitat Conservation Plans
Why Conserve Habitat?
 Critical to species’ survival
 Protection applies to more than just the
species of interest
 Know more about habitat hot spots and
distribution than about species distributions
 Know habitat loss and degradation are
major reasons for endangerment
Modern Views of Populations
and Habitats
 Review Sinks, Sources, and Metapopulation
Concepts
– ESC 450
– Chapter 5 in NRC’s “Science and the ESA”
– Pulliam 1988 (if you have not read it--DO SO
TODAY!)
• dispersal from source can result in large and
growing sink even given <1
Metapopulation Review
 Subpopulations connected by dispersal (Levins 1969)
 Good way to describe structure and dynamics of
populations scattered across a landscape in spatially
isolated patches
– common in managed landscapes
 Some sub-populations may be sinks and some may be
sources, but this is only a special case of general
metapopulation model
– core-satellite or simultaneous sink-source may be more
common (Doak and Mills 1994; Doncaster et al. 1997)
Key Messages for Endangered
Species Management
 Extinction of subpopulations in
metapopulation is to be expected
 Subpopulation dynamics may be controlled
by dynamics of other subpopulations
– rescue by dispersal
– need to ID sources or cores
 Functioning metapopulation may be
necessary for species to remain extant
– Acorn Woodpeckers in New Mexico
• (Stacey and Taper 1992)
Another Key: Habitat is Not
Constant in Space or Time
 It is a “shifting mosaic”
(Bormann and Likens 1979, Botkin
and Sobel 1975)
– habitat composition in landscape changes naturally
• usually slowly
• BWCA (continual change at replacement rate every 2-4
centuries from glaciation and succession)
– fire has return rate of 20-200 years
– GPP may ~ Respiration at ecosystem scale (steady state),
but individual stands change frequently
Management Implications of
Shifting Mosaics
Clear-cutting
Fire
Wind
Time (White Mountains, NH; Bormann and Likens 1979)
 Land management usually decreases time between
disturbances
• may also affect spatial arrangement by increasing edge
 Endangered species may need change or may need
specific disturbance state
– Kirtland’s Warbler and Red-cockaded Woodpecker
Do We Really Know Habitat Needs?
80 Spring
Important
Males
Females
10
20
AG CN
80
CR CS SS WI
Fall
Adults
Hatch
Year
20
AG CN
CR CS SS WI
 Van Horne (1983)
– abundance  quality
 Yong et al. (1998)
– Wilson’s Warblers in New
Mexico
– Habitat needs differ from
spring to fall (breeeding to
migration)
• cottonwood not used in
spring
– Habitat needs differ from
adults to subadults
• ag for juveniles, willow for
adults
Critical Habitat Designation
 At listing (after 1978, not retroactive)
 Takes into account ECONOMIC impacts
– Can be opted out if “non prudent” or not determinable
• non-prudent can be for any reason
 To date <20% of species have critical habitat
designated (NRC)
Is Critical Habitat Needed?
 USFWS argues “no”
– Sect 7 consultations already require fed agencies to avoid
jeopardizing the species by modifying habitat
– Sect 9 prohibits take by the public, which has been
equated with habitat destruction (Sweet Home)
 But regulation of habitat by disallowing take
is less absolute than designating Critical
Habitat
– requires “no likelihood of jeopardy” but critical
habitat cannot by “adversely modified”
Possible Improvements to Critical
Habitat
 “Survival Habitat” (NRC)
– temporary designation at time of listing
– habitat needed to support current population or
ensure short-term (25-50 year) survival,
whichever is larger
– No economic evaluation goes into it
– Allows management options to be preserved
until recovery plan and formal critical habitat is
proposed
Habitat Conservation Plans
 More likely to be the way habitat is
protected on non-federal lands (rather than
designation of critical habitat)
 Allows non-federal landowners to get
incidental take permit (Sect 10(a))
– implementation of HCP “will, to the maximum
extent practicable, minimize and mitigate the
impacts of such taking” and “not appreciably
reduce the likelihood of survival and recovery
of the species in the wild”
HCPs as a Solution to a Problem
 Services view HCPs as a way to balance a
citizen’s right to use their property with the
nation’s interest in conserving rare and
endangered species
 Goal is to create “creative partnerships”
between landowners wanting to develop
their land and our natural heritage
Increase in HCPs
 San Bruno Mtn. Cal
(1983)
 Over 200 in 1997, 200
more in preparation
 Range in size
200
180
160
140
120
No. of
100
HCPs
80
60
40
20
0
– 1/2 acre lot (Fl. Scrub Jay)
– 170,000 acres
• Plum Creek Timber
– 100 years, 285listed and
unlisted species
90 91 92 93 94 95 96
– 1.6 million acres
• WA DNR
– 70-100 years, 200 species
The HCP Process (USFWS 1998)
 Plan Development
–
–
–
–
permit application ($25)
the plan
document of compliance with NEPA
implementation agreement
 Review
– service
– public (published in Federal Register)
 Monitoring
– service monitors compliance with HCP
Contents of HCP (USFWS 1998)
 Species covered (listed and non-listed)
 Assessment of impacts of take
 How take will be monitored, minimized, and
mitigated
 Plan for funding the proposed monitoring and
mitigation
 Alternatives to take and why they are not being
adopted
 Argument that taking will not reduce the
species’ survival and recovery
Criticisms of HCPs (Minett & Cullinan 1997;
Kaiser 1997)
 Not based on science
– We need to know a lot about management of species to
decide on long-term management strategies
• PVAs of all species in plan
 Not Flexible (esp. if “no surprises”)
– Adaptive management framework that allows
adjustment as more information comes in
• need a carefully designed and well funded scientific
management program for the ecosystem
– that can be expensive, but costs are predictable
• Provide public funds for SURPRISES
More Criticisms (Minett & Cullinan 1997;
Kaiser 1997)
 Separate plans for single landowners results in
fragmented approach to conservation
– not a problem if landowners hold large areas
– can result in “high grading”
• first HCP gets by with as much as possible
• subsequent HCPs have to conserve species given
what is already provided
– they may have to provide more expensive habitat or
curtain operations to a greater extent than first planer
• plans rely on particular use of adjoining land
– what if it fails?
 Multi-owner (regional) HCPs would be better
More Recent HCP Evaluation
 The National Center for Ecological Analysis
and Synthesis reviewed many HCPs and
their results echo those previously
mentioned
 View their report here to better understand
HCPs and evaluate their scientific validity
HCPs are not Recovery Plans
 Another criticism is that HCPs often do little
for the listed species
– Requirement is that plan MINIMIZES and
MITIGATES take
• they do not have to contribute to RECOVERY
• alternatives easily dismissed
– Rota’s proposed HCP would take 1/2 of Mariana
Crow’s habitat!
– Balcones Canyonlands HCP (Texas) provided
12,000 ha, but science report called for 53,000 ha
• black-capped vireo is likely to go locally extinct
Limited Public Participation
 A serious criticism from environmental
organizations
– Years of negotiation between service and
landowner prior to review
– Service does not have to use public comments
obtained during review when making their final
decision
– Too much invested in negotiations to change
after public comments
– Environmental organizations are out of loop
and don’t like it
Making HCPs Better
(Kaiser 1997)
 Require plan to boost, not reduce, populations
of listed species
 Initial plan developed by scientists with no
vested interests in planning area
 Wait for recovery plan before HCP is approved
– allows range-wide coordination of efforts
 Allow for adjustment even with “no surprise”
– public funding for surprises
– good monitoring and adaptive response
An Example of a “Good Plan”
(NRC and Kaiser 1997)
 California’s Natural Community
Conservation Plan
• southern coastal sage
– Regional
• provides protection for more than just listed
(gnatcatcher) species so future plans are less likley
– Blueprint drafted by panel of independent
scientists
• functioned as interim plan
• pointed out needs for research on dispersal,
demography, genetics, autecology before final plan
Interim NCCP Directions
 Slow development (<5% of native landscape)
 No net loss of habitat VALUE
– Stick to tenets of conservation biology
• increase species distribution
• large, aggregated, non-fragmented, interconnected,
roadless blocks of habitat are best
– Rank habitat according to tenets
• best habitat is managed as reserves
• secondary priority is conferred on moderate habitat
adjoining reserves
References
 Minett, M. and T. Cullinan.1997. A citizen’s guide to
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HCPs. National Audubon Society. Washington DC.
USFWS. 1998. Www.fws.gov/r9endspp/hcpplan.html
Kaiser, J. 1997. When a habitat is not a home. Science
276:1636-1638.
Bormann, FH. And GE Likens. 1979. Catastrophic
disturbance and the steady state in northern hardwood
forests. Am. Scientist 67:660-669.
Doncaster, CP, Clobert, J, Doligez, B, Gustafsson, L, and
E. Danchin. 1997. Balanced dispersal between spatially
varying local populations: an alternative to the source-sink
model. Am. Nat. 150:425-445.
More References
 Levins, R. 1969. Some demographic and genetic
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consequences of environmental heterogeneity for
environmental control. Bull. Entomol. Soc. Am. 15:237240.
Stacey, PB. And M. Taper. 1992. Environmental variation
and the persistence of small populations. Ecol. Appl. 2:1829.
Pulliam, HR. 1988. Sources, sinks, and population
regulation. Am. Natural. 132:652-661.
Doak, DF and LS Mills. 1994. A useful role for theory in
conservation. Ecology 75:615-626.
Botkin, DB. And MJ. Sobel. 1975. Stability in timevarying ecosystems. Am. Nat. 109:625-646.
More References
 Yong, W., Finch, DM, Moore, FR, and JF Kelly. 1998. Stopover
ecology and habitat use of migratory Wilson’s Warblers. Auk 115:829842.
 Van Horne, B. 1983. Density as a misleading indicator of habitat
quality. JWM 47:893-901.