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Level II (Monitoring)

The action and focus for these species is monitoring (M). Declining population trend and habitat loss are not known to be significant at this point. Includes species of which Wyoming has a high percentage of and responsibility for the breeding population (R), species whose stability (S) may be unknown (S?), species that are peripheral (P) for breeding in the habitat or state, or additional knowledge (K) may be needed.

Common Loon

Primary Habitat Type: Wetlands and Aquatic

SPECIES & STATUS	VEGETATION COMPOSITION	VEGETATION STRUCTURE	ABIOTIC FACTORS	LANDSCAPE FACTORS	SPECIAL FACTORS
Common Loon (COLO) Gavia immer Level II M	~Grassy shorelines and islands, including grasses, sedges, and rushes	~Territories usually include an area of shallow water with emergent vegetation ~Lakeshore at least partially forested	~Requires lakes of ≥10 acres; nesting success is poorer on lakes that are <25 acres ~Water clarity (minimum visibility of 3 to 4 feet) is important, as loons are visual predators ~Water depth >6 feet to prevent winter kill of fish ~Lakes that remain ice-free for ≥4 months to allow young to fledge ~Islands or secluded shorelines (e.g. quiet bays) for nesting ~Steep slope adjacent to shoreline for an underwater approach to the nest	~Territory may range from 10 to 500 acres ~Nest at elevations between 6,000 and 8,000 feet	~Sensitive to human disturbances and water level fluctuations ~Requires abundant populations of small to mid-sized fish ~Strong fidelity to breeding territory ~Will use artificial nesting platforms ~Winters south to northern Mexico on coasts, bays, and estuaries

Found on lakes across most of Wyoming during migration, but nests only in northwestern Wyoming. Lakes that are suitable for loon breeding habitat include those that are at least 10 acres (4 ha), although reproductive success is better on lakes that are greater than 25 acres (10 ha); are free of human disturbances or have areas that are secluded from human activity; are between 6,000 and 8,000 feet (1830 and 2440 m) in elevation; have clear water with a minimum visibility of 10 to 13 feet (3 to 4 m), as loons are visual predators; have islands or protected shore areas for nesting and raising young; have abundant populations of small to mid-sized fish; are greater than 6 feet (2 m) deep to prevent winter kill of fish; and remain ice free for at least 4 months to allow young to fledge. Ideal nesting lakes also generally have at least partially forested, rocky shorelines; an area of shallow water with emergent vegetation; and a steep slope adjacent to the shoreline for an underwater approach to the nest. Builds a primitive platform nest of mud and vegetation, placed on the ground no more than 3 to 6 feet (1 to 2 m) from the water's edge. Will use artificial nesting platforms. Eggs (1 to 2, 89 mm) are olive-brown or olive-green, and sparsely marked with black or brown. Feeds by diving from the surface and pursuing fish; may also take some aquatic invertebrates, especially crustaceans. Winters south to northern Mexico on coasts, bays, and estuaries. Is threatened by loss of nesting habitat. May be threatened by acid rain, which kills fish that are used as food. Is intolerant of human disturbances, which may cause nest desertion. Nests may be flooded by boat wakes or water level fluctuation. Other species that may benefit from habitat management for this species include the Northern Harrier, Sandhill Crane, and Canada Goose.

Population Objectives

1) Breeding Bird Survey (BBS) data from 1968 through 2002 are inadequate to determine population trends for the Common Loon in Wyoming. Determine population trend data by implementing “Monitoring Wyoming’s Birds: The Plan for Count-based Monitoring”.

Habitat Objectives

1) Maintain the suitability of currently used Common Loon nesting territories.

2) Protect large, clear, deep lakes throughout the state from habitat degradation.

3) Maintain water quality to sustain substantial populations of small to mid-sized fish as a food source for Common Loons.

Recommendations

1) Protect all current and traditional Common Loon nesting sites from development and degradation. Because loons exhibit strong year-to-year fidelity to previous nest sites, there is a high probability that they will reuse nests and nurseries if these areas are not developed or degraded. When possible, two or three alternate sites with characteristics of preferred nesting areas should be protected on each breeding lake. Small islands should receive complete protection from development. Undeveloped buffer zones of at least 500 feet (150 m) should be left on either side of nest sites and nursery areas.

2) Protect all areas with characteristics suitable for nesting and chick rearing, even if actual use has not been documented.

3) Maintain vegetation buffer zones to block siltation, pesticide, and fertilizer runoff into lakes.

4) Maintain stable water levels throughout the nesting season in lakes where Common Loons are breeding. Rising water levels can flood nests and, although small drawdowns may be acceptable if distances between nests and the water's edge are not greatly increased, significant lake level subsidence may cause nest desertion or loss of newly-hatched chicks.

5) Avoid disturbing nesting areas, as loons are very sensitive to human disturbance. During times of human intrusion, incubating loons slip off nests, swim underwater, and emerge at a distance, which leaves the nests open to predation. During disturbances after hatching, chicks are dropped off the adult's back, and are left near the shore, where they may be vulnerable to predation.

6) Restrict access to Common Loon nesting territories during the breeding season. Limit or prohibit activities such as boating, fishing, swimming, camping, and picnicking near nest sites and in nursery areas. In some cases, posting signs to discourage visitors may be effective. However, signs may also draw attention to nesting sites and may be ineffective when enforcement is not possible. In such cases, efforts to educate the public may be the most reasonable method of reducing disturbance.

7) Educate the public about the natural history and conservation needs of loons. Most human-related loon problems stem from ignorance, not intent. Public education can include posters and information at marinas and other lake access points; informational brochures; press releases; and lectures, slide programs, and other presentations. Visitors can be required to attend an educational program before entering a wilderness or recreational area with breeding loons.

8) Establish boat engine horsepower limitations and/or speed limits on lakes where Common Loons are breeding, and strictly enforce boating restrictions. Motorboats and personal watercraft (e.g. jet skis) produce waves that can destroy nests and create disturbances that can cause egg or chick loss.

9) Consider known loon nest sites and nesting territories when establishing new campgrounds or campsites. Close present campsites or campgrounds near known loon nesting sites and designate specific campsites well away from nesting loons. Since loons prefer to nest on small islands when they are available, camping should be prohibited on islands, and other uses of islands should be discouraged or, if necessary, prohibited.

10) Consider installing and maintaining artificial nest platforms where fluctuating water levels or the lack of suitable nest sites is limiting Common Loon reproduction. Artificial nest platforms may improve nesting success on lakes that lack natural islands, have poor shoreline nesting habitat, or have a history of low productivity. Platforms rise and fall with water levels and can counteract extreme fluctuations on lakes where loons are not considered in water management plans. Platforms alone are unlikely to induce nesting on unoccupied lakes or territories, and should not be viewed as an easy alternative to the protection of natural nest sites. Artificial nest platforms should not be used where loons are already nesting successfully or where natural nest sites are already available, because they require yearly maintenance, increase dependence on long-term human interest, and attract human attention.

11) Construct artificial nest platforms of five 6- to 8-foot (1.8- to 2.4-m) cedar logs, approximately 8 inches (20 cm) in diameter. Notch the logs at both ends, shape them into a square frame with one cross-log, and join them with #20 galvanized spikes. Staple a 5x5-foot (1.5x1.5 m) piece of heavy plastic snow fencing mesh to the bottom of each frame, wrapping it halfway up the sides from underneath, and making sure there are no protrusions or wild ends that might injure a bird. Attach 3/16-inch (0.5-cm) wire cable to two opposite corners of the raft with cable clamps and secure the cables to two cement block anchors. Fill the raft with 4 to 6 bushels of duff, loose leaves, twigs, and roots, and plant it with low-growing vegetation indigenous to the natural nesting area. Because loons begin nesting very soon after ice-out, install nesting platforms within 2 weeks after ice-out. Place platforms in areas of minimal human disturbance, out of the direct path of prevailing summer winds and waves, in 10 to 30 feet (3 to 10 m) of water and approximately 100 to 165 feet (30 to 50 m) from shore. Completed platforms may last for 3 or 4 years, but in some cases, especially in unprotected locations, they may blow to shore during the spring or fall and have to be pulled back into the lake or replaced.

American White Pelican

Primary Habitat Type: Aquatic

SPECIES & STATUS	VEGETATION COMPOSITION	VEGETATION STRUCTURE	ABIOTIC FACTORS	LANDSCAPE FACTORS	SPECIAL FACTORS
American White Pelican (AWPE) Pelecanus erythro-rhynchos Level II M	~Prefers open areas of annual grasses and forbs, shrubs, ~Prefers nonvegetated areas for nesting	~Nests on flat islands without vegetation >3 feet or other tall obstructions	~Breeds on large freshwater lakes ~Requires islands isolated from mammalian predators for nesting ~Prefers gravel or sandy, unconsolidated substrates for nesting	~Adults may travel to lakes, rivers, and marshes >50 miles away from the nest site to feed	~Nests colonially and is highly social ~Very sensitive to human disturbance during nesting ~Nest site tenacity between years is low ~Winters south through lowlands to Nicaragua

Uses a variety of aquatic habitats for foraging and can be found on rivers, streams, lakes, ponds, and marshes throughout Wyoming. Nests at only a few specific locations in the state, as breeding habitat is much more restrictive. Nests colonially on large freshwater lakes, and requires islands isolated from mammalian predators. Colonies are usually located on flat, open ground near water. Creates a scrape on bare ground or a mound of soil and debris. Prefers gravel or sandy, unconsolidated substrates for nesting. Eggs (2, 90 mm) are white, often nest-stained. Feeds mostly on nongame fish, such as such as carp and suckers, and salamanders and crayfish; trout and other game fish comprise less than 5% of its diet. Feeds while swimming, dipping its bill into the water to catch fish in its pouch. Often feeds in small groups that may cooperatively herd fish toward shallow water where they are easier to catch. Adults may travel over 50 miles (80 km) from the nest site to feed. Winters south through lowlands to Nicaragua. Is primarily threatened by combinations of changing water levels and human disturbance. Pesticides have caused eggshell thinning in some areas. Other species that may benefit from habitat management for this species include the California Gull, Caspian Tern, and Double-crested Cormorant.

Population Objectives

1) Determine statewide population trend data by implementing “Monitoring Wyoming’s Birds: The Plan for Count-based Monitoring”.

2) Breeding Bird Survey (BBS) data from 1968 through 2002 indicate American White Pelicans have been detected on 31 BBS routes in Wyoming, including 15 routes on which they were observed a minimum of 3 years.

a) Maintain American White Pelicans on the 31 BBS routes on which they were observed (Figure 23).

b) Maintain the average number of individuals observed per route over the past 5 years at a level equal to or above the average number of individuals observed during all years the route was run.

3) Maintain a minimum of two nesting colonies in Wyoming, including one nesting colony outside of Yellowstone National Park.

Figure 23. Bold lines indicate Breeding Bird Survey routes on which American White Pelicans have been observed from 1968 through 2002.

Habitat Objectives

1) Maintain water levels at lakes where American White Pelicans nest.

2) Maintain substantial populations of fish as a food source for American White Pelicans.

Recommendations

1) Minimize water level fluctuations during the nest-building through fledging stages of American White Pelicans. Rising water levels can flood nests and lake level subsidence may connect islands to the lakeshore, exposing eggs or young to mammalian predators.

2) Protect any colony sites currently in use, regardless of the size of the site or the number of pelicans present.

3) Protect all remaining suitable aquatic habitat in the state. The success of American White Pelicans depends, in part, on their flexibility in choosing nesting areas. This makes protection of all suitable lakes and islands important because pelicans may use a particular site only occasionally, but when they do, it may be their only chance of nesting success.

4) Maintain ample foraging areas within range of colonies. Protect foraging habitat from widespread permanent flooding or drainage.

5) Avoid disturbing nest sites during the breeding season, as colonies are very sensitive to human disturbance. Restrict entry at colonies with excessive human disturbance. In some cases, posting signs to discourage visitors may be effective. However, signs may also draw attention to colony sites and may be ineffective when enforcement is not possible. Efforts to educate the public may be the most reasonable method of reducing disturbance.

6) Maintain a minimum disturbance-free buffer zone of 330 to 590 feet (100 to 180 m) at breeding colonies.

7) Maintain vegetation buffer zones to block siltation, pesticide, and fertilizer runoff into aquatic habitat. This is particularly important where American White Pelican colonies are adjacent to agricultural land, and vulnerable to contamination from agricultural runoff.

8) Consider building and maintaining artificial islands in areas where a lack of suitable nesting habitat is limiting American White Pelican reproduction. Construct islands of soil or dredged materials, at least ¼ acre (0.1 ha) in size. Islands should be flat and situated well offshore for protection from mammalian predators and human disturbance.

Harlequin Duck

Primary Habitat Type: Montane Riparian

SPECIES & STATUS	VEGETATION COMPOSITION	VEGETATION STRUCTURE	ABIOTIC FACTORS	LANDSCAPE FACTORS	SPECIAL FACTORS
Harlequin Duck (HARD) Histrionicus histrionicus Level II M, P		~Dense streamside shrubs ~Overhanging vegetation	~Remote mountain streams ~Good water quality	~Sections of stream with low gradient (<5%), braided channels, sections with swift currents ~Mid and late succession	~Strong fidelity to breeding streams and natal areas ~Very sensitive to human disturbance in breeding territories ~Requires abundant aquatic insects ~Arrives in WY late April; by mid July most males and nonbreeding females depart; females with young depart from mid August to late September ~Winters in coastal North America

Found only in the northwestern corner of Wyoming. Prefers cold, shallow, rapid mountain streams away from concentrated human activities. Nesting habitat includes very low gradient stream sections with dense shrubs lining the banks, braided channels, swift currents, and water rich in aquatic insects. Nests on the ground or in a tree cavity. Nest is a mass of down concealed in a rock crevice or cavity along a stream. Eggs (6 to 8, 58 mm) are pale buff or cream colored. Is a diving duck that eats crustaceans, mollusks, insects, and fish. Winters in marine waters along the Pacific coast. Its presence on a particular stream is an indicator of high water quality. Nesting success is impacted by stream degradation due to sedimentation, channelization, logging, incompatible recreation, and incompatible livestock grazing. Other species that may benefit from habitat management for this species include the Bald Eagle, Calliope Hummingbird, Willow Flycatcher, American Dipper, Lazuli Bunting, Veery, and Bullock’s Oriole.

Population Objectives

1) Breeding Bird Survey (BBS) data from 1968 through 2002 are inadequate to determine population trends for the Harlequin Duck in Wyoming. Determine population trend data by implementing “Monitoring Wyoming’s Birds: The Plan for Count-based Monitoring”.

Habitat Objectives

1) Maintain water quality in high elevation mountain habitats by eliminating or limiting habitat changes that are detrimental to Harlequin Ducks, such as tie hack logging, sediment loading, and development.

Recommendations

1) In areas where Harlequin Ducks nest, ensure that old growth occurs in and around premier streams, and that recreation, grazing, forest management, and logging do not impact preferred nesting habitat.

2) In areas where Harlequin Ducks nest, maintain high water quality and stream stretches with high densities of invertebrates.

3) Avoid clearing debris from high elevation mountain streams to ensure Harlequin Duck nesting and feeding habitat is present.

4) Avoid trail construction and maintenance, other management activities, or intense recreation along known Harlequin Duck breeding streams during the first 7 to 10 days after hatching, as they are especially vulnerable to disturbance during this time. If necessary in areas of intense activity, close stream sections where Harlequin Ducks are known to breed while the chicks are flightless (June to early August).

Merlin

Primary Habitat Type: Low Elevation Conifer

SPECIES & STATUS	VEGETATION COMPOSITION	VEGETATION STRUCTURE	ABIOTIC FACTORS	LANDSCAPE FACTORS	SPECIAL FACTORS
Merlin (MERL) Falco columbarius Level II M	~Ponderosa pine ~Douglas-fir ~Open woodlands close to grasslands or shrub-steppe	~Trees spaced well apart whose lower 8 to 10 feet are bare of branches ~Open understory	~Sometimes in cities and towns