[Federal Register Volume 62, Number 120 (Monday, June 23, 1997)]
[Proposed Rules]
[Pages 33960-33965]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-16395]
[[Page 33959]]
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Part III
Department of the Interior
_______________________________________________________________________
Fish and Wildlife Service
_______________________________________________________________________
50 CFR Part 21
Migratory Bird Permits; Proposed Depredation Order for the Double-
Crested Cormorant; Proposed Rule
Federal Register / Vol. 62, No. 120 / Monday, June 23, 1997 /
Proposed Rules
[[Page 33960]]
DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 21
RIN 1018-AE11
Migratory Bird Permits; Proposed Depredation Order for the
Double-Crested Cormorant
Agency: Fish and Wildlife Service, Interior.
Action: Proposed rule.
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SUMMARY: The U.S. Fish and Wildlife Service (hereinafter Service)
proposes to implement a depredation order for the double-crested
cormorant. In those States in which double-crested cormorants have been
shown to be seriously injurious to commercial freshwater aquaculture,
and when found committing or about to commit depredations upon
aquaculture stock, persons engaged in the production of aquaculture
commodity stocks would be allowed, without a Federal permit, to take or
cause to be taken such double-crested cormorants as might be necessary
to protect aquaculture stocks.
DATES: Comments must be submitted on or before August 22, 1997.
ADDRESSES: Comments may be mailed to Chief, Office of Migratory Bird
Management (MBMO), U.S. Fish and Wildlife Service, Department of the
Interior, ms 634--ARLSQ, 1849 C Street, NW, Washington, D.C. 20240.
Comments will be available for public inspection during normal business
hours in room 634, Arlington Square Building, 4401 N. Fairfax Drive,
Arlington, Virginia.
FOR FURTHER INFORMATION CONTACT: Paul R. Schmidt, Chief, MBMO, U.S.
Fish and Wildlife Service, (703) 358-1714.
SUPPLEMENTARY INFORMATION:
Background
Double-crested cormorant populations are at an all-time high in the
modern era, and commercial aquaculturists (especially catfish farmers)
in many parts of the country are experiencing economic losses due to
cormorant depredation. Three avenues currently are available to
aquaculturists for dealing with cormorant depredation problems: (1)
birds can be harassed (with shotgun blasts, fire crackers, propane
cannons, or other scare devices) without a Federal permit; (2) ponds
can be fitted with physical barriers (or exclusionary devices) such as
wire or mesh netting that prevent birds from landing; and (3) private
aquaculturists and State-operated fish hatcheries can apply to the
Service for a permit to kill cormorants.
The Service is the Federal agency with the primary responsibility
for managing migratory birds. The Service's authority is based on the
Migratory Bird Treaty Act (MBTA) (16 U.S.C. 703-711), which implements
conventions with Great Britain (for Canada), the United Mexican States
(=Mexico), Japan, and the Soviet Union (=Russia). The double-crested
cormorant is afforded Federal protection by the 1972 amendment to the
Convention for the Protection of Migratory Birds and Game Animals,
February 7, 1936, United States--Mexico, as amended, 50 Stat. 1311,
T.S. No. 912, as well as, the Convention Between the United States of
America and the Union of Soviet Socialist Republics [=Russia]
Concerning the Conservation of Migratory Birds and Their Environment,
November 26, 1976, 92 Stat. 3110, T.I.A.S. 9073 (16 U.S.C. 703, 712).
The take of double-crested cormorants is strictly prohibited except as
may be permitted under regulations implementing the MBTA. In addition
to, Federal statutes, the double-crested cormorant may also be
protected by State regulations.
Regulations governing the issuance of permits for migratory birds
are authorized by the MBTA and subsequent regulations (Title 50, Code
of Federal Regulations, Parts 13 and 21). Regulations in Subpart D of
Part 21 deal specifically with the control of depredating birds.
Section 21.41 outlines procedures for issuing permits. Sections 21.43
through 21.46 deal with special depredation orders for specific species
of migratory birds to address particular problems in specific
geographical areas, establishing a precedent for species and geographic
treatments in the permitting process. Service policies for issuing
depredation permits for aquaculture were described by Trapp et al.
(1995).
Federal responsibility for the management of injurious wildlife,
including migratory birds, lies with the Animal Damage Control (ADC)
program of the U.S. Department of Agriculture's Animal and Plant Health
Inspection Service. The primary authority for ADC activities is the
Animal Damage Control Act of 1931, as amended, 46 Stat. 1468 (7 U.S.C.
426-426c). Animal Damage Control activities are conducted at the
request of, and in cooperation with, other Federal, State, and local
agencies; private organizations; and individuals. Management
responsibilities of ADC in the cormorant-aquaculture conflict were
reviewed by Acord (1995).
Commercial Aquaculture Industry
Aquaculture, the cultivation of finfish and invertebrates in
captivity, has grown exponentially in the past several decades (Price
and Nickum 1995). The five principal aquaculture fish species in the
United States are catfish, trout, salmon, tilapia, and hybrid striped
bass. There are also two categories of non-food fish: baitfish and
ornamental fish (U.S. Department of Agriculture 1995). While each of
these industries has its own unique set of bird depredation problems,
they all share a basic concern for developing and implementing the best
methods for protecting fish stocks from predation.
The market for channel catfish (Ictalurus punctatus) is the largest
segment of the aquaculture industry, and the one which is perhaps most
susceptible to predation by cormorants. The catfish accounts for about
one-half of the value of aquaculture in the United States.
The number of catfish farms in the United States increased 44
percent between 1982 and 1990 (from 1,494 to 2,155). Most of this
increase occurred between 1982 and 1987. Growth was fairly steady
throughout the 1980s, with production leveling off in the past few
years. Production was estimated at 224,875 metric tons (247,933 short
tons, or 496 million pounds, or 225 million kilograms) worth $353
million in 1993 and is expected to expand 5-7 percent annually due to
increasing sales prices.
Mississippi is the center of catfish production, producing 75-80
percent of the United States output. Alabama, Arkansas, and Louisiana
are also major producers. California, Florida, Illinois, Kentucky,
Missouri, North Carolina, Oklahoma, South Carolina, Texas, and Virginia
also produce catfish and all have, or will have, problems with fish-
eating birds. In the four principal catfish-producing States, the
number of farms increased 67 percent between 1982 and 1992 (from 794 to
1,193); increases in individual States were 24 percent in Alabama (327-
405), 40 percent in Mississippi (316-442), 67 percent in Arkansas (115-
191), and 330 percent in Louisiana (36-155).
The more than 64,300 hectares (158,840 acres) of catfish ponds in
the United States in 1995 represented a 2.3-fold increase from about
28,300 hectares (69,900 acres) in production in the 1970s. The four
principal catfish-producing States accounted for 93 percent of the
total area, with Mississippi alone accounting for about 60 percent.
Catfish ponds range in size from 4-14 hectares (10-35 acres) each, with
a mean size of 5 hectares (12
[[Page 33961]]
acres). Farms with 100 hectares (247 acres) in production are not
uncommon, and many are more than 400 hectares (990 acres). In the Delta
region of Mississippi, catfish farms average about 100 hectares (247
acres) of ponds, with a typical rectangular pond size of 8 hectares (20
acres); ponds are shallow, ranging from 1-2 meters (3.3-6.6 feet) deep.
The large size of the ponds makes them highly visible to fish-eating
birds from the air, and the high stocking levels (from 5,000 to more
than 150,000 fish/hectare [or 2,000 to more than 60,700 fish/acre],
Glahn and Stickley 1995) make them especially attractive to cormorants.
The catfish industry's practice of using large ponds developed in the
early 1970s when cormorant numbers were low.
The physical dimensions of the ponds are the secret to the catfish
farmers' success (as well as the source of today's predation problem).
The most efficient production ponds are circular, but they can not be
harvested as easily. So, the ponds are generally rectangular and can be
as wide as 80-95 meters (262-312 feet). At harvest time, crews drag 100
meter (325 foot) wide seine nets strung between tractors on both sides
of the rectangular ponds along the length of each pond. Undersize fish
slip through the mesh and are harvested the next year. Because catfish
farmers stock more than one year class of fish in a pond, it is not
possible to drain the ponds and to reconfigure them to a size and shape
that can be covered easily with bird-excluding nets. Also, the levees
between the ponds are not wide enough to install extensive net
structures and yet leave room for tractors to maneuver. Thus, several
economic factors (e.g., low profit margin, the cost to modify the
ponds, and a heavy investment in current harvest technologies) combine
to preclude major changes in pond shape and size at the present time.
Population Status of the Double-crested Cormorant
The size of the North American breeding population of the double-
crested cormorant was recently estimated at about 360,000 pairs (Hatch
1995). Using values derived from the published literature of 1-4
nonbreeding birds for each breeding pair yields an estimated total
population of about 1-2 million birds (Hatch 1995).
The double-crested cormorant breeds widely throughout much of
coastal and interior North America. As of 1992, it had been found
breeding in 40 of the 50 United States, all 10 Canadian provinces, and
in Mexico, Cuba, and the Bahamas (Hatch 1995). However, it is not
uniformly distributed across this broad area. Sixty-one percent of the
breeding birds belong to the Interior population, while another 26
percent belong to the Atlantic population. Two major areas of
concentration are apparent in the vast range of the Interior
population: (1) the prairie lakes of Alberta, Manitoba, and
Saskatchewan (which account for 69 percent of the Interior population);
and (2) the U.S. and Canadian Great Lakes (accounting for another 12
percent).
Seven political units account for 70 percent of the North American
breeding birds, with Manitoba alone accounting for 36 percent. Thirty
(52 percent) of the 58 political units listed by Hatch (1995) each
harbor fewer than 100 breeding pairs. In the catfish-producing States
identified by Price and Nickum (1995), only Florida and California have
sizeable breeding populations.
In the south-central United States (Arkansas, Louisiana,
Mississippi, and west Tennessee), the double-crested cormorant has been
known since pre-colonial times and has been recorded as an occasional
breeder throughout the swampy forests of the region since at least the
early 1800s (Jackson and Jackson 1995). Jackson and Jackson predicted
that (in the absence of major limiting factors) the cormorant will once
again become a regular member of the mid-South breeding avifauna, with
birds dispersed more widely because of reservoir construction and with
concentrations expected in the vicinity of aquaculture facilities.
The double-crested cormorant has always been widely distributed as
a breeding species. The only suspected instance of range expansion in
the 20th century is in the United States and Canadian Great Lakes,
which apparently were colonized by birds expanding eastward from the
Canadian prairies beginning with Lake Superior about 1913 and ending
with lakes Erie and Ontario in the late 1930s (Weseloh et al. 1995). It
is possible, however, that these events represented recolonization of
former (but previously undocumented) breeding localities from which the
species was extirpated before 1912. For example, although Barrows
(1912: 67) knew of no breeding records for Michigan, he noted that it
was ``generally distributed over the State during the migrations''
(with specimens from almost every county) and speculated that
``probably there are few sheets of water any size within our limits
which are not visited by this bird at least occasionally.''
The core of the wintering range (i.e., the regions of greatest
density) did not change appreciably between 1959-1972 and 1959-1988
(Root 1988: 11, Sauer et al. 1996b). Cormorant wintering populations
are concentrated in coastal States and Provinces, from North Carolina
to Texas in the east and from California to British Columbia in the
west. In the mid-South, there also are appreciable concentrations
inland from the coast (e.g., east Texas, eastern Oklahoma, southeastern
Arkansas, west-central Mississippi, and northeastern Alabama). Of the 9
catfish-producing States for which Christmas Bird Count data are
available, 6 have indices of relative abundance that exceed the
national mean; the median abundance in these 6 States (including the
major catfish-producers of Alabama, Louisiana, and Mississippi) was 2.0
times the national mean (range: 1.4-9.6).
The scattered occurrence of early winter stragglers throughout much
of the interior of the continent as far north as Minnesota and southern
Saskatchewan (Sauer et al. 1996b) is probably a natural phenomenon of
longstanding (i.e., it probably does not represent a northward
expansion of the wintering range). As evidence of this, we find that 11
percent of 227 winter recoveries (December-February 1923-1988) of birds
banded in Saskatchewan, Lake Huron, and eastern Lake Ontario were from
latitudes north of the major catfish-producing States of Alabama,
Arkansas, Louisiana, and Mississippi (Dolbeer 1991). Forty percent of
these 227 winter recoveries are from 1 deg. blocks of latitude and
longitude that intersect the Gulf Coast and another 22 percent are from
degree blocks that intersect the main stem of the Mississippi River.
Analysis of 5,589 band recovery records for the period 1923-1988
(Dolbeer 1991) revealed that southward movement from areas north of
latitude 42 deg.N occurs primarily in October and November. Cormorants
of all ages are at their greatest median distance from northern nesting
areas--about 1,900 kilometers (1,200 miles)--from December through
March.
Cormorants nesting in Canada and the northern United States from
Alberta to the Gulf of St. Lawrence migrate in winter primarily to the
southern United States between Texas and Florida. There is considerable
mixing and overlap in winter of nesting populations from widely
divergent areas. From 38 to 70 percent of the birds from Saskatchewan
through the Great Lakes region winter in the lower Mississippi Valley
(States of Arkansas, Louisiana, and Mississippi) as do 10 percent of
the birds from such disparate areas as Alberta and the New England
coast (Dolbeer 1991). In other words, the major catfish-producing
States of the lower Mississippi may be envisioned as lying at the apex
of an
[[Page 33962]]
inverted triangle, with cormorants from a 3,000 kilometer (1,860 mile)
expanse of breeding range being funneled into the region in the winter
by topographic features and the flow of the major rivers. In commenting
on this funneling effect, Jackson and Jackson (1995) noted that ``It is
a most unfortunate coincidence that the very heart of the catfish-
farming industry is located in the Mississippi Delta at the confluence
of the Arkansas and Mississippi rivers.''
Our knowledge of double-crested cormorant population trends before
1959 is based on fragmented and largely anecdotal accounts from
scattered portions of the range. Syntheses of much of this information
(Hatch 1995, Weseloh et al. 1995, and Jackson and Jackson 1995) reveal
the following general patterns: (1) by 1900, cormorant numbers had been
reduced, and their range possibly restricted, by human persecution and
the extensive drainage and degradation of natural wetlands; (2) the
widespread construction of reservoirs and impoundments (beginning in
the 1920s), in concert with sport fish stocking programs and the
creation of refuges and other conservation lands (beginning in the
1930s), had beneficial effects on cormorant numbers; (3) the widespread
use of DDT and other pesticides (beginning in the 1940s) had
devastating effects on cormorant reproductive success, with the result
that populations reached their lowest point in the mid-1970s; (4) the
ban on DDT in 1972 and the general decrease in levels of environmental
contamination, in concert with development of the catfish industry in
the mid-1970s, created a favorable environment for the growth of
cormorant populations.
Quantitative information on double-crested cormorant population
trends is available from three sources: (1) Breeding Bird Survey data
(1966-1994), (2) Christmas Bird Count data (1959-1988), and (3)
published accounts of censuses of breeding colonies. Trend information
from these sources is discussed in the following paragraphs:
(1) Between 1966 and 1994, the continental breeding population
increased at an estimated rate of 6.1 percent/year (Sauer et al.
1996a). The very high rate of growth in the early years (13.0 percent/
year), and to a lesser extent for the entire period, is partly an
artifact of the extremely small population in the early years of the
survey period (late 1960s and early 1970s). Compared to the earlier
(1966-1979) time period, the growth of the continental and Canadian
populations appears to have slowed appreciably in the later (1980-1994)
period; however, the U.S. population has continued to show a
significant rate of increase in the 1980s and 1990s, apparently due
primarily to the continued rapid growth of populations in the mountains
and plains States. The only significant declines noted were in the West
Coast region (1966-1994) and in North Dakota (1980-1994), although the
West Coast trend appears to be contradicted by rather dramatic site-
specific increases in British Columbia, Washington, and California
(Carter et al. 1995). Most of the recent increase in numbers has
occurred within the known historical breeding range (Hatch 1995).
(2) Between 1959 and 1988, the continental wintering population
increased at an average rate of 7.3 percent/year (Sauer et al. 1996b);
significant increases were registered for 17 of the 20 States or
Provinces for which data were available. Trends are available for 9 of
the primary catfish-producing States; 6 of these States (Alabama,
Louisiana, Mississippi, Oklahoma, Texas, and Virginia) have trends
(median 16 percent, range 12-19 percent) that are well above the
continental average. Most of the localities in the mid-South for which
information is available show dramatic population increases between the
mid-1970s and the early 1990s, with the trends paralleling a similar
magnitude of growth in the area of catfish ponds in the region during
the same period (Jackson and Jackson 1995).
(3) Rather dramatic increases in breeding pairs are documented at
colonies in the Great Lakes (Weseloh et al. 1995), the St. Lawrence
River and associated waters (Chapdelaine and Bedard 1995), New England
(Krohn et al. 1995), the West Coast (Carter et al. 1995), and elsewhere
(Weseloh et al. 1995). The trends documented by these studies generally
parallel those from the Breeding Bird Survey and the Christmas Bird
Count.
Foraging Behavior of the Double-crested Cormorant at Aquaculture
Facilities
Daily Movements and Activity Budgets. In the Mississippi Delta,
cormorants fly an average of 16 kilometers (25 miles) from their night
roosts to feeding sites. Each bird spends about 18 percent of daylight
hours feeding; 88 percent of their foraging is done at catfish ponds
and 12 percent near roost sites. The average cormorant forages for 60
minutes each day, but spends just 20 minutes underwater in actual
pursuit of fish (King et al. 1995).
Feeding Rates. Feeding rates may be dependent on the size and
abundance of the available fish and the metabolic demands of the birds,
and can be quite variable. Actively feeding cormorants in commercial
catfish ponds capture an average of about 5 fish/cormorant/hour
(Stickley 1991, Stickley et al. 1992), but can vary from 0-28 (Schramm
et al. (1984). Partly because of this variability, the rate of 5 fish/
cormorant/hour reported by Stickley et al. (1992) is highly skewed; the
median was only 2 fish/cormorant/hour, and the mean was equaled or
exceeded at only 3 (21 percent) of the 14 ponds studied. Stickley et
al. (1992) did not find a significant relationship between the mean
number of cormorants present and the number of catfish consumed, but
ponds with 40 or more cormorants generally had a feeding rate of 1 or
fewer fish/cormorant/hour. Similarly, cormorant feeding rates were not
related to the density of fingerling catfish, density of all catfish
(all size classes combined), or mean length of fish .
Diet Composition. Cormorants eat a wide variety of prey items, and
there is thus a great deal of variation in prey composition, both
geographically and seasonally. Nearly all of the published information
on diet composition at aquaculture facilities has been gathered in the
vicinity of catfish farms in the southeastern United States (Bivings
1989, Conniff 1991, Glahn and Stickley 1992, Glahn et al. 1995, and
Glahn and Brugger 1995). These studies show that, among birds actively
feeding on catfish ponds, the average proportion of catfish in the
winter diet (by number) is most commonly in the range of 50-55 percent.
The proportion varies seasonally from less than 30 percent in October
and November to more than 80 percent in February, March, and April.
Prey Size. Although cormorants are capable of taking catfish up to
42 centimeters (16 inches) in length (Campo et al. 1993), studies
repeatedly have shown that the vast majority of catfish caught by
cormorants at commercial facilities are in the range of 7-20
centimeters (3-8 inches), with most averaging about 10-15 centimeters
(4-6 inches) (Schramm et al. 1984, Stickley 1991, Stickley et al.
1992). This range of prey sizes is remarkably close to that of prey
taken by cormorants in natural freshwater habitats. In five such
studies (Durham 1955, Hirsch 1986, Haws 1987, Hobson et al. 1989, Campo
et al. 1993), prey size ranged from 6-21 centimeters (2-8 inches), with
a median value of about 12 centimeters (5 inches).
Prey Preferences. Lacking a precise knowledge of the species
composition and size distribution of the prey population, it is
impossible to make definitive statements about prey preferences.
However a few tendencies
[[Page 33963]]
are apparent. For example, the 10-15 centimeter (4-6 inch) fingerling
catfish preferred by cormorants in one study represented about 64
percent of the catfish (by number) in the ponds (from Stickley et al.
1992), suggesting that the birds were merely preying on the most
readily available fish. In this same study, 1 of the 14 ponds contained
gizzard shad in addition to catfish. Nineteen shad were consumed for
every catfish eaten, even though the pond contained about 5,100
fingerling catfish/hectare (2,100/acre). The apparent preference for
gizzard shad in this instance may be related to their being more easily
caught, handled, and swallowed by cormorants (the mean handling time
for catfish was 6-7 times greater than that of gizzard shad).
Daily Food Consumption Rates. Estimates of daily food consumption
rates of cormorants at or in the vicinity of aquaculture facilities in
the southeastern United States vary widely, from 208-504 grams (7-17
ounces, or 0.4-1.1 pounds) (Schramm et al. 1984, Schramm et al. 1987,
Bivings et al. 1989, Conniff 1991, Brugger 1993, Glahn and Brugger
1995). The most widely accepted figure is about 320 grams (11 ounces,
or 0.7 pounds) of fish/day, of which about one-half (or 160 grams [5.5
ounces, or 0.35 pounds]) would be catfish (Brugger 1993).
Impacts of Double-crested Cormorants on Aquaculture
With the exception of catfish, quantitative accounts of the impacts
of cormorants on freshwater aquaculture stocks generally are lacking.
The fairly large body of literature that has developed in the past 12
years represents an attempt to assess the impacts of cormorants on the
commercial catfish industry. Synopses of the pertinent literature are
given in the following paragraphs.
In the past, cormorants have been reported only infrequently at
fish hatcheries. For example, questionnaire surveys conducted in 1977
(Scanlon et al. 1979) and 1984 (Parkhurst et al. 1987) indicate that
cormorants were considered to be problems at only 4-5 percent of these
facilities nationwide. Of the more than 90 other (including non-avian)
species mentioned as predators, 45-50 percent were listed more
frequently than cormorants. Purported instances of cormorant damage to
hatchery fish in Texas (Dukes 1987) include the loss of 90 percent of
the smallmouth bass (Micropterus dolomieui) 2-year-old brood stock at
the Jasper facility.
The frequency of occurrence of cormorants at a given catfish pond
is a function of many interacting factors, including: (1) size of the
regional cormorant population; (2) the number, size, and distribution
of catfish ponds; (3) the size distribution, density, health, and
species composition of fish populations in the catfish ponds; (4) the
number, size, and distribution of ``natural'' wetlands in the immediate
environs; and (5) the size distribution, density, health, and species
composition of ``natural'' fish populations in the surrounding
landscape. Cormorants are adept at seeking out the most favorable
foraging sites. As a result, cormorants rarely are distributed evenly
over a given region, but rather tend to be highly clumped or localized.
For example, in 27 weekly surveys at 50 catfish ponds in Humphreys
County, Mississippi, 1987-1988, cormorants were observed at only 9 of
the 50 ponds and only on 14 occasions (Hodges 1989). Thus, it is not
uncommon for many fish farmers in a region to suffer little or no
economic damage from cormorants, while a few farmers experience
exceptionally high losses.
Cormorants clearly respond in a positive way to the presence of
shallow-water ponds stocked with high densities of easy-to-capture prey
fish. For example, within two weeks of stocking 2 ponds in Hendry
County, Florida, with 5-20 centimeter (2-8 inch) fingerling catfish, 12
cormorants were feeding in the ponds and roosting on nearby poles. A
nearby 2.5 hectare (6 acre), 2.5-meter (8-foot) deep pond, stocked with
75,000 3-8 centimeter (1-3 inch) fish in August 1980, had attracted 13
cormorants by September. These birds continued to feed at the pond
throughout the fall and winter, and in spring 1981 they nested in a
nearby cypress dome. By November 1981, about 50 cormorants were feeding
in the pond (Schramm et al. 1984). The positive response of cormorants
to the presence of shallow-water ponds stocked with high densities of
easy-to-capture prey fish (as illustrated above) is clearly a major
factor responsible for their impacts in a variety of aquaculture
situations (e.g., baitfish ponds in Minnesota, koi ponds in Missouri
and elsewhere, ornamental fish ponds in Florida, and catfish pods in
the southeastern United States and elsewhere).
Assuming averages of 5 fingerling catfish consumed/cormorant/hour
and 30 cormorants/pond (a constant number of feeding birds present
throughout an 8 hour day), the catfish population of a typical pond in
the Mississippi Delta (51,000 fish/hectare in a 8-hectare pond, which
is equivalent to 20,650 fish/acre in a 20-acre pond) would be halved in
167 days (Stickley et al. 1992). However, if actual values were nearer
the median values of 2 fish/cormorant/hour and 15 birds/pond (from
Stickley et al. 1992), the number of days required for the cormorants
to reduce the population by half would be increased to 850 days (a 5-
fold increase).
Of 281 catfish farmers queried on the Mississippi Delta in 1988
(Stickley and Andrews 1989), 87 percent felt that they had a bird
problem. Moderate to heavy cormorant activity (defined as at least 25
birds/day) was reported by 57 percent of Delta farmers. Losses to birds
(harassment costs plus value of fish lost) were estimated at $5.4
million (3 percent of total sales).
Overall, there appears to be little conflict between cormorants and
the food- or game-fish industry in Florida (Brugger 1992), but losses
of food fish, primarily catfish, can be locally severe (Brugger 1995);
for example, cormorants were responsible for the loss of up to 50
percent of the fingerling catfish in open 0.125 hectare (0.31 acre)
ponds during 1991 at the University of Florida.
Although fish of commercial value made up only a small percentage
of the diet of cormorants collected in the vicinity of aquaculture
facilities in central and southeast Arkansas from mid-October to early
December, the finding of a few fish of very high value (e.g., grass
carp with wholesale value of about $4.00 and koi worth $5.00-10.00
each) suggests that cormorant depredations can be locally or seasonally
severe.
On the Mississippi Delta, cormorants consumed an estimated 18-20
million catfish during the winters of 1989-1990 and 1990-1991, which
was equivalent to 842-939 metric tons (928-1,035 short tons, or 1.86-
2.07 million pounds, or 844-939 thousand kilograms). Based on the cost
of replacing these fish, annual losses to the catfish industry were
estimated at $1.8-2.0 million, which corresponds to about 4 percent of
the estimated catfish standing crop each year. Although losses were
documented over a six-month period, the majority (about 64-67 percent)
occurred in February and March (Glahn and Brugger 1995).
At catfish farms in Oklahoma (with about 324 hectares [800 acres]
of surface water in production) in 1993, cormorants consumed an
estimated 7,196 kilograms (15,900 pounds, or 7.9 short tons) of catfish
valued at $14,000-36,000 (depending on size of the fish consumed), or
about 3-7 percent of Oklahoma catfish sales (Simmonds et al. 1995).
[[Page 33964]]
Cormorant Depredation Permits
Depredation permits to take double-crested cormorants at commercial
aquaculture facilities have been issued by the Fish and Wildlife
Service since 1986. Composite data for a recent two-year period (1993-
1994) show that about 8,200 cormorants were taken each year by 2,261
permit holders. Cormorants represented the majority (about 57 percent)
of the total number of birds killed nationwide; two-thirds of the
cormorants were taken in the southeastern region of the United States,
with substantial numbers also taken in the southwest and the upper
Midwest.
Between 1989 and 1996, the number of permits issued to take double-
crested cormorants in the southeastern United States more than
quadrupled, from 50 to 215 (Coon et al. 1996). The reported take of
4,000-8,000 birds annually has had no noticeable effect on the size of
the regional wintering population.
Mastrangelo et al. (1995) noted that the reported take never
exceeded 68 percent of the authorized take and attributed this to the
frightening effect that lethal control has on bird behavior. Hess
(1994) described a recent study in which catfish farmers at three
complexes in Mississippi were authorized (under Fish and Wildlife
Service permits) to remove as many as 2,500 cormorants in a 19-week
period. Participants were supplied with ammunition and encouraged to
kill as many birds as allowed by the permit. The fact that only 290
birds had been killed by the end of the project was attributed to a
learned behavior by the birds to avoid areas where they might be shot
(Hess 1994).
Environmental Consequences of Proposed Action
Cormorant Population. The proposed action (a depredation order) is
expected to result in a moderate increase in the number of double-
crested cormorants taken at aquaculture facilities. The impact is
expected to be localized (e.g., possible reductions in the size of
wintering populations in the immediate vicinity of catfish farms). To
calculate the potential maximum harvest, we can assume that 42
cormorants (the average number reported taken by holders of depredation
permits in the southeastern United States, 1989-1995; from Coon et al.
1996) will be shot at each of the about 2,200 catfish farms in the
United States. The resultant annual take of 92,400 birds will represent
about 5-10 percent of the continental population. This level of take
will be more than offset by the recruitment of young birds into the
population; a reproductive success of 1.7-3.2 young/nest (Duffy 1995)
will equate to a minimum recruitment, at current population levels, of
612,000 young into the population each year. In reality, the proposed
action is expected to result in only a modest increase in the number of
double-crested cormorants taken at aquaculture facilities.
Socio-Economic. The proposed action is expected to reduce the
direct economic losses caused by cormorants at commercial aquaculture
facilities. It also will enhance the effectiveness of current nonlethal
control programs, thus reducing overall damage control costs to
producers. The proposed depredation order will reduce paperwork and
costs associated with administering the current permit system and will
promote quicker and more efficient depredation control operations by
shifting responsibility to the individual aquaculturists. A depredation
order will demonstrate cooperation between the Federal agency
responsible for protecting and enhancing wildlife (Service), the
Federal agency responsible for dealing with wildlife damage issues
(ADC), and the individual producers in dealing with a problem that has
the potential to expand far beyond the wildlife management arena.
Other Fish-Eating Birds. Although the proposed action does not
authorize the taking of other fish-eating birds, it is possible that a
few birds could be taken accidentally on occasion. The two species that
are most likely to be confused with the double-crested cormorant are
the neotropic cormorant (Phalacrocorax brasilianus) and the anhinga
(Anhinga anhinga). These species have foraging habits very much like
those of the double-crested cormorant and may occur on or in the
vicinity of catfish ponds in the Gulf Coast States. The likelihood of
other fish-eating birds being mistaken for double-crested cormorants
and shot accidentally is not expected to increase above that which
presently occurs . However, because of a projected increase in the
number of producers conducting lethal control operations for
cormorants, it is possible that there will be a slight to moderate
increase in the actual number of other fish-eating birds (especially
neotropic cormorants and anhingas) taken accidentally. Any negative
effects on these species would be extremely localized, and long-term
impacts on populations would be unlikely.
Endangered and Threatened Species. Negligible impacts to endangered
or threatened species are expected under the proposed action. Few
endangered or threatened species have ever been taken by aquaculturists
with depredation permits. The likelihood of endangered or threatened
species being taken by accident is not expected to increase under the
proposed action.
Public Comments Invited
The policy of the Department of the Interior is, whenever
practical, to afford the public an opportunity to participate in the
rulemaking process. Accordingly, interested persons may submit written
comments, suggestions, or objections regarding this proposal to the
location identified in the addresses caption. Comments must be received
on or before August 22, 1997. Following review and consideration of the
comments, the Service will issue a final rule on these proposed
amendments.
National Environmental Policy Act
In accordance with the National Environmental Policy Act of 1969,
the Service has prepared an Environmental Assessment of the proposed
action, and a Finding of No Significant Impact has been issued. Copies
of these documents are available from the Chief, Office of Migratory
Bird Management, U.S. Fish and Wildlife Service, 4401 North Fairfax
Drive, ms 634--ARLSQ, Arlington, VA 22203.
Endangered Species Act Consideration
Consultations will be initiated to ensure that actions resulting
from this proposal will not likely jeopardize the continued existence
of endangered or threatened species or result in the destruction or
adverse modification of their critical habitat. Findings from these
consultations will be included in a biological opinion and may cause
modification of some regulatory measures proposed in this document. The
final rule will reflect any such modifications.
Regulatory Flexibility Act, Executive Order (E.O.) 12866 and
Paperwork Reduction Act
Based on the economic impacts discussed above, the Service has
determined under the Regulatory Flexibility Act of 1980 (5 U.S.C. 601
et seq.) that this rulemaking would not have a significant effect on a
substantial number of small entities, which include businesses,
organizations and governmental jurisdiction. This rule was not subject
to review by the Office of Management and Budget under E.O 12866.
The Service examined the proposed rule under the Paperwork
Reduction Act of 1995 and found that it does not
[[Page 33965]]
contain information collection requirements.
Unfunded Mandates
The Service has determined and certifies, in compliance with the
requirements of the Unfunded Mandates Act, 2 U.S.C. 1502 et seq., that
this rulemaking will not impose a cost of $100 million or more in any
given year on local or State government or private entities.
Civil Justice Reform--Executive Order 12988
The Department, in promulgating this proposed rule, has determined
that these regulations meet the applicable standards found in Sections
3(a) and 3(b)(2) of Executive Order 12988.
References Cited
A complete list of all references cited herein is available upon
request from John L. Trapp, Office of Migratory Bird Management, U.S.
Fish and Wildlife Service, 4401 North Fairfax Drive, ms 634--ARLSQ,
Arlington, Virginia 22203.
Author
The primary author of this proposed rule is John L. Trapp, Office
of Migratory Bird Management.
List of Subjects in 50 CFR Part 21
Exports, Hunting, Imports, Reporting and recordkeeping
requirements, Transportation, Wildlife.
Proposed Regulation Promulgation
Accordingly, the Service hereby proposes to amend part 21, subpart
D, of subchapter B, chapter I, title 50 of the Code of Federal
Regulations, as set forth below:
PART 21--[AMENDED]
1. The authority citation for part 21 continues to read as follows:
Authority: Pub. L. 95-616, 92 Stat. 3112 (16 U.S.C. 712(2)).
Subpart D--Control of Depredating Birds
2. Part 21, subpart D, is amended by adding Sec. 21.47 to read as
follows:
Sec. 21.47 Depredation order for double-crested cormorants at
aquaculture facilities.
In all States in the contiguous 48 States except Arizona,
California, Colorado, Idaho, Kansas, Montana, Nebraska, Nevada, New
Mexico, North Dakota, Oregon, South Dakota, Utah, Washington, and
Wyoming, persons actually engaged in the production of aquaculture
commodity stocks may, without a Federal permit, take double-crested
cormorants when found committing or about to commit depredations to
aquaculture stocks on the premises owned or occupied by such persons:
Provided that:
(a) Double-crested cormorants may be taken only by shooting, and
only when necessary to protect freshwater commercial aquaculture and
State-operated hatchery stocks from depredation; none of the birds so
taken may be sold or removed from the area where killed; and all dead
birds must be buried or incinerated within this area, except that any
specimens needed for scientific purposes as determined by the Director
must not be destroyed.
(b) Double-crested cormorants may be shot at freshwater commercial
aquaculture facilities or State-operated hatcheries only in conjunction
with an established non-lethal harassment program approved by the
Animal Damage Control program of the U.S. Department of Agriculture's
Animal and Plant Health Inspection Service.
(c) Double-crested cormorants may be shot only within the
boundaries of freshwater commercial aquaculture facilities or State-
operated hatcheries.
(d) No person operating under the provisions of this section may
use decoys, taped calls, or other devices to lure birds within gun
range.
(e) Any person exercising the privileges of this section must
permit, at all reasonable times, Federal or State wildlife enforcement
officers access to the premises on which the operations have been or
are being conducted; and must furnish to the officers whatever
information they may reasonably require concerning the operations,
including a log of the number of double-crested cormorants killed.
(f) Nothing in this section authorizes the killing of double-
crested cormorants contrary to the laws or regulations of any State,
and none of the privileges of this section may be exercised unless the
person possesses the appropriate State permits, when required.
(g) Unless specifically extended, the authority granted in this
section will automatically expire on April 30, 2005.
Dated: June 9, 1997.
William Leary,
Acting Deputy Assistant Secretary for Fish and Wildlife and Parks.
[FR Doc. 97-16395 Filed 6-20-97; 8:45 am]
Billing Code: 4310-55-F
