7939

• UCREFRP Catalog Number: 7939
• Author: Sidle, J. G.
• Title: Forum, Critical Habitat Designation
• USFW Year: 1987
• USFW - Doc Type: Is It Prudent?
• Copyright Material: YES

Critical Habitat Designation 433

Table 1. Number of endangered and threatened species in the United States listed annually, 1967-1986.
Year Mammals Birds Reptiles Amphibians Fishes Snails Clams Crustaceans Insects Plants Total
1967 12 33 3 2 17 0 0 0 0 0 67
1970 4 22 7 I 10 0 0 0 0 0 44
1972 1 0 0 0 0 0 0 0 0 0 I
1973 2 2 0 1 1 0 0 0 0 0 6
1975 0 3 I 0 3 0 0 0 0 0 7
1976 4 I 0 1 0 0 22 0 8 0 36
1977 I 3 5 1 5 0 I 0 0 4 20
1978 1 1 6 0 2 7 0 1 0 19 37
1979 2 0 0 0 0 0 0 0 0 34 36
1980 0 0 3 I 4 0 0 0 5 2 15
1981 0 0 0 0 0 1 0 0 0 3 4
1982 0 0 1 0 3 0 0 2 0 6 12
1983 3 0 0 0 1 0 0 I 0 2 7
1984 3 8 0 1 5 0 0 0 0 14 31
1985 7 3 0 0 13 0 1 0 I 35 60
1986 1 3 2 0 6 0 0 1 0 24 37
Total 41 79 28 8 70 8 24 5 14 143 420
Species listed prior to 1973 under the Endangered Species Preservation Act of 1966 and the Endangered Species Conservation Act of 1969 are
protected by the Endangered Species Act of 1973, as amended. The Table does not include the 12 species that have been delisted because either
they were judged extinct or the original data were in error.

times, however, proposed CHDs are modified to con-
form to legal boundaries or contours. A species pro-
posed with CHD usually takes about one additional
year or longer for final listing than a species proposed
for listing without CHD.
CHDs currently include about 1860 km of streams
and coastal waterways, 45 springs and outflows, 60 km
of beaches, 22 caves and mines, and 4,058,300 ha of
land and other wetlands. About 2.5 million ha (64%)
of the 4,058,300 ha is CH for the gray wolf in
northern Minnesota and in Isle Royale National Park,
Michigan. Other large CHDs are for the American
crocodile (561,500 ha), Everglade snail kite (Rostrhamw
sociabilis Plumbeus) (353,800 ha), California condor
(224,700 ha), and the whooping crane (145,000 ha).
These CH figures are estimates because precise mea-
surements ofCH areas are not always given in the Fed-
eral Register or listed species recovery plans. The
smallest CHD is 600 m2 for Carex specuicola in Arizona.
Most of the CHDs comprise the majority of the cur-
rent range of the species. Although 420 species are
currently listed in the USA, CHDs exist for only 96
(23%) species (Table 2). Four of 7 listings in 1983, 8 of
31 listings in 1984, 24 of 60 listings in 1985, and 4 of
37 listings in 1986 contained CHD.

Prudence and Benefits of Critical
Habitat Designation

Currently, CHD must be made to the maximum
extent prudent at the time of a species' listing. If avail-
able information for a CHD is not sufficient at the

time of listing, the government has one additional year
to make a CHD. CHD can be waived entirely if the
FWS or NMFS has determined that it is "not prudent"
when one or both of the following situations exist: (a)
The species is threatened by taking or other human
activity, and identification of CH can be expected to
increase the degree of such threat to the species, or (b)
such CHD would not be beneficial.
The reason for not designating CH for most plants
is usually the real or perceived threat of taking or van-
dalism that might be exacerbated by the required pub-
lication of detailed CH locations in the Federal Register.
Cacti, for example, are prized by collectors and none
of the 23 listed cacti have CHDs. However, there is no
CHD for many plants that have no history of taking or
vandalism and are not particularly attractive to col-
lectors. It is believed in some cases that published CH
locations would attract vandals in the form of off-road
vehicles deliberately driving over the plants and their
habitats.
Another reason for not designating CH centers
around the usefulness of such designation. Bean
(1983) maintains that CHD gives advance notice of
those areas where federal actions will require espe-
cially dose scrutiny. This is true, but for many species
there is no CHD because the areas where the species
occur can be identified to affected federal agencies
without CHD. Therefore, there is presumably no ben-
efit from a CHD.
For example, there is no CHD for the Maguire
primrose (Primula maguiret) because the US Forest Ser-
vice has been informed of the listing, is aware of the