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KABAM Version 1.0 User's Guide and Technical Documentation - Appendix E - Selection of Bird Species of Concern and Corresponding Biological Parameters

(Kow (based) Aquatic BioAccumulation Model)

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Appendix E. Selection of Bird Species of Concern and Corresponding Biological Parameters

Bird species of concern were identified in order to define default parameters (for body weight and diet composition) to represent birds in KABAM. Bird species were considered to be of concern for pesticide exposures through aquatic bioaccumulation if their diets incorporated freshwater aquatic animals. Specific species were identified using the Smithsonian handbooks' Birds of North America (Eastern and Western Regions) (Alsop 2001a and 2001b). These handbooks contain information on the ranges, taxonomy, habits, feeding preferences, and habitats of birds located in the continental United States, Canada, and Alaska.

A review of this source identified over 40 bird species of concern that fall into 11 families. These families include:

  • Accipitridae (eagles, hawks and kites)
  • Alcedinidae (kingfisher)
  • Anatidae (ducks)
  • Ardeidae (herons, egrets and bitterns)
  • Gruidae (cranes)
  • Pelecanidae (pelicans)
  • Phalacrocoracidae (cormorants)
  • Podicipedidae (grebes)
  • Rallidae (rails)
  • Scolopacidae (sandpiper) and
  • Threskiornithidae (ibis).

Descriptions of these families are provided below.

It should be noted that this review was not intended to be inclusive of every relevant species or family of birds inhabiting North America. Rather, the intention of this review was to identify birds that may consume aquatic animals containing pesticides that bioaccumulate in aquatic ecosystems. Information from identified bird species and families was used to define the default parameters representing birds in the KABAM tool. These default parameters are described below.

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  • E.1 Bird Family Descriptions

    • E.1.1. Accipitridae (Eagles, Hawks and Kites)

      Most species of this family prey upon terrestrial rodents; however, several rely upon aquatic animals for their diet (Table E1). These species include the osprey (Pandion haliaetus) and the bald eagle (Haliaeetus leucocephalus) (Alsop 2001a and 2001b). Ospreys fly over freshwater and saltwater areas and catch fish from the surface of the water using their feet. Body weights of osprey range from 1.25 to 2.0 kg (USEPA 1993). Bald eagles eat fish, rodents, birds, and carrion. Body weights of adult bald eagles range 3.0 - 5.8 kg (USEPA 1993). An additional member of this family, the snail kite (Rostrhamus sociabilis), has a subspecies that is federally listed as endangered (USFWS 2008). This species is known to occur in wetlands of Florida, where the bird eats snails (Alsop 2001a). The average body weight of this bird is 0.38 kg (Dunning 1984).

      Table E1
      Body Weights and Diets of Species of Accipitridae that Prey upon Aquatic Animals
      Species (scientific name) Body weight
      (kg)
      Diet
      Snail kite (Rostrhamus sociabilis) 0.381 snails2
      Osprey (Pandion haliaetus) 1.25-2.003 fish3
      Bald eagle (Haliaeetus leucocephalus) 3.00 - 5.803 fish, rodents, birds, and carrion3

      1Dunning 1984; 2Alsop 2001a and 2001b; 3USEPA 1993

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    • E.1.2. Alcedinidae (kingfisher)

      One species of this family, the belted kingfisher (Ceryle alcyon) is widely distributed throughout North America, inhabiting freshwater areas such as lakes, rivers, and ponds, as well as marine coastal areas. This species feeds primarily upon fish, but its diet also includes amphibians, insects, and crayfish. Body weights of this species range 0.13-0.22 kg (USEPA 1993; Table E2).

      Table E2
      Body Weights and Diets of Species of Alcedinidae that Prey upon Aquatic Animals
      Species (scientific name) Body weight
      (kg)
      Diet
      Belted kingfisher (Ceryle alcyon) 0.13-0.221 primarily fish, but also amphibians, insects and crayfish1

      1USEPA 1993

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    • E.1.3. Anatidae (Ducks)

      There are many species of ducks that are widely distributed in North America (Table E3). Ducks predominantly inhabit freshwater areas such as lakes, rivers, wetlands, and ponds. Their diets include a wide variety of aquatic organisms, such as aquatic insects, insect larvae, snails, amphibians, fish, crayfish, mollusks, plankton, and aquatic plants (Alsop 2001a and 2001b). Body weights of ducks vary based on the species, with a range of 0.3-2.0 kg for ducks inhabiting freshwater areas (Dunning 1984).

      Table E3
      Body Weights and Diets of Species of Anatidae that Prey upon Aquatic Animals
      Species (scientific name) Body weight
      (kg)1
      Diet2
      Cinnamon teal (Anas cyanoptera) 0.36-0.41 seeds, aquatic insects, rice, algae, snails, crustaceans
      Bufflehead (Bucephala alboela) 0.30-0.55 aquatic insects and insect larvae, snails, small fish, seeds
      Wood duck (Aix sponsa) 0.64-0.91 plants, animals, snails, tadpoles, salamanders
      Hooded merganser (Lophodytes cuculatus) 0.54-0.91 fish, crustaceans, aquatic insects, aquatic animals
      Lesser scaup (Aythya affinis) 0.54-1.05 plants and animals
      Common goldeneye (Bucephala clangula) 0.80-1.40 mollusks, crustaceans, insects, aquatic plants
      Mallard (Anas platyrhynchos) 0.72-1.58 plants, insects, mollusks, crustaceans
      Red-breasted merganser (Mergus serrator) 0.91-1.31 fish
      Common merganser (Mergus merganser) 1.05-2.05 small fish, mollusks, crustaceans, aquatic insects, some plants

      1Dunning 1984; 2Alsop 2001a and 2001b

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    • E.1.4. Ardeidae (Herons, Egrets and Bitterns)

      This family includes species of herons, bitterns and egrets, several of which inhabit waters of North America (Table E4). Their habitats include freshwater areas such as lakes, rivers, ponds, wetlands, and streams, as well as marine coastal areas. These birds wade through water to spear their food with their beaks. Their diets include fish, crustaceans, amphibians, snakes, crayfish, and insects (Alsop 2001a and 2001b, USEPA 1993). Individuals of this family range in weight from 0.08 to 2.9 kg, depending upon the species (Dunning 1984, USEPA 1993).

      Table E4
      Body Weights and Diets of Species of Ardeidae that Prey upon Aquatic Animals
      Species (scientific name) Body weight
      (kg)1
      Diet2
      Least bittern (Ixobrychus exilis) 0.08-0.09 fish, insects
      Green heron (Butorides virescens) 0.212 fish, aquatic invertebrates
      Snowy egret (Egretta thula) 0.35-0.40 crustaceans, insects, fish
      Little blue heron (Egretta caerulea) 0.32-0.45 small vertebrates, crustaceans, large insects
      American bittern (Botaurus lentiginosus) 0.52-1.07 frogs, small eels, small fish, snakes, salamanders, crayfish, small rodents, water bugs
      Yellow-crowned night heron (Nyctanassa violacea) 0.72-0.85 crustaceans, fish, shellfish
      Black crowned night heron (Nycticorax nycticorax) 0.73-1.01 fish, mollusks, small rodents, frogs, snakes, crustaceans, plants, eggs, birds
      Great egret (Ardea alba) 0.80-1.07 fish, frogs, snakes, crayfish, large insects
      Great blue heron (Ardea herodias) 1.87-2.88 fish, other aquatic animals

      1Dunning 1984; 2Alsop 2001a and 2001b

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    • E.1.5. Gruidae (Cranes)

      Cranes inhabit freshwater wetlands and marshes. These birds eat fish, frogs, small mammals, mollusks, crustaceans, and plants (Alsop 2001a and 2001b). Two species of cranes, i.e., the whooping crane (Grus americana) and the Mississippi sandhill crane (Grus canadensis pulla), are federally listed as endangered (USFWS 2008). Body weights of the whooping crane and sandhill crane range 2.5-6.7 kg (Dunning 1984) (Table E5).

      Table E5
      Body Weights and Diets of Species of Gruidae that Prey upon Aquatic Animals
      Species (scientific name) Body weight
      (kg)1
      Diet2
      Whooping crane (Grus americana) 5.44-6.36 fish, frogs, small mammals, mollusks, crustaceans, and plants
      Sandhill crane (Grus canadensis) 2.45-6.70 plants and animals

      1Dunning 1984; 2Alsop 2001a and 2001b

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    • E.1.6. Pelecanidae (Pelicans)

      There is one species of pelican that inhabits freshwater aquatic habitats of North America: the American white pelican (Pelecanus erythrorhynchos ). Their habitats include freshwater areas such as lakes, rivers, ponds, wetlands and streams, as well as marine coastal areas. The diet of these birds includes fish (Alsop 2001a and 2001b). The average weight of the American white pelican is 7.5 kg (Dunning 1984) (Table E6).

      Table E6
      Body Weights and Diets of Species of Pelecanidae that Prey upon Aquatic Animals
      Species (scientific name) Body weight
      (kg)
      Diet
      American white pelican (Pelecanus erythrorhynchos) 7.51 fish2

      1Dunning 1984; 2Alsop 2001a and 2001b

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    • E.1.7. Phalacrocoracidae (Cormorants)

      Of the species of cormorants inhabiting North America, the double-breasted cormorant (Phalacrocorax auritus) is the most widespread, inhabiting freshwater areas such as lakes, rivers, ponds, as well as marine coastal areas. Cormorants dive for their prey, which includes fish, crustaceans, and amphibians (Alsop 2001a and 2001b). The average weight of the double-breasted cormorant is 1.8 kg (Dunning 1984).

      Table E7
      Body Weights and Diets of Species of Phalacrocoracidae that Prey upon Aquatic Animals
      Species (scientific name) Body weight
      (kg)
      Diet
      Double-breasted cormorant (Phalacrocorax auritus) 1.60-2.041 fish, crustaceans and amphibians2

      1Dunning 1984; 2Alsop 2001a and 2001b

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    • E.1.8. Podicipedidae (Grebes)

      Several species of grebes reside in the continental United States (Table E8). Their habitats include freshwater areas such as lakes, rivers, ponds, wetlands, and streams, as well as marine areas. These birds forage for aquatic insects, crustaceans, and fish by diving underwater (Alsop 2001a and 2001b). They range in weight 0.2-1.8 kg (Alsop 2001a and 2001b, Dunning 1984).

      Table E8
      Body Weights and Diets of Species of Podicipedidae that Prey upon Aquatic Animals
      Species (scientific name) Body weight
      (kg)1
      Diet2
      Eared grebe (Podiceps nigricollis) 0.22-0.37 aquatic insects
      Pied-billed grebe (Podilymbus podiceps) 0.34-0.55 aquatic insects, small fish, crustaceans
      Horned grebe (Podiceps auritus) 0.33-0.53 fish, crustaceans, aquatic insects
      Western grebe (Aechmorphorus occidentalis) 0.80-1.82 fish
      Clark's grebe (Aechmophorus clarkia) 1.502 fish

      1Dunning 1984; 2Alsop 2001a and 2001b

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    • E.1.9. Rallidae (Rails)

      Rail species inhabit freshwater areas such as lakes, rivers, ponds, wetlands and streams as well as saltwater marshes of North America. These species feed upon crustaceans, aquatic insects, snails, fish, and plants (Alsop 2001a and 2001b). Individuals of this family range in weight from 0.07 to 0.49 kg (Dunning 1984) (Table E9). One species from this family, the clapper rail (Rallus longirostris) is federally listed as an endangered species and is known to occur in Arizona, California, Nevada, and Utah (USFWS 2008).

      Table E9
      Body Weights and Diets of Species of Rallidae that Prey upon Aquatic Animals
      Species (scientific name) Body weight
      (kg)1
      Diet2
      Sora (Porzana carolina) 0.08 plants, insects, spiders, small crustaceans, snails
      Virginia rail (Rallus limicola) 0.07-0.12 insects (primarily), worms, crustaceans, small fish
      King rail (Rallus elegans) 0.25-0.49 plants, aquatic invertebrates, aquatic vertebrates
      Clapper rail (Rallus longirostris) 0.25-0.35 crabs, crustaceans, worms, amphibians, reptiles, mollusks, small fish, aquatic insects

      1Dunning 1984; 2Alsop 2001a and 2001b

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    • E.1.10. Scolopacidae (Sandpipers)

      Many species of sandpipers inhabit freshwater aquatic habitats of North America (Table E10). These habitats include lakes, rivers, ponds, wetlands, and streams. Their diets include aquatic invertebrates, insects, crustaceans, small fish, amphibians, and mollusks (Alsop 2001a and 2001b). Body weights of sandpipers range 0.02- 0.70 kg (Dunning 1984).

      Table E10
      Body Weights and Diets of Species of Scolopacidae that Prey upon Aquatic Animals
      Species (scientific name) Body weight
      (kg)1
      Diet2
      Least sandpiper (Calidris minutilla) 0.022 insects and larvae, crustaceans
      Spotted sandpiper (Actitis macularia) 0.03-0.06 invertebrates, small fish
      Wilson's phalarope (Phalaropus tricolor) 0.072 larvae, crustaceans, seeds
      Greater yellow legs (Tringa melanoleca) 0.12-0.22 small fish, insects and larvae, crabs, snails
      Willet (Catoptrophorus semipalmatus) 0.22 aquatic insects, mollusks, small fish
      Long-billed curlew (Numenius americanus) 0.57-0.70 aquatic insects, larvae, mollusks, crustaceans, small amphibians

      1Dunning 1984; 2Alsop 2001a and 2001b

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    • E.1.11. Threskiornithidae (Ibis)

      Ibis inhabit freshwater areas such as lakes, rivers, ponds, wetlands, and streams, as well as marine coastal areas of North America. These species are wading birds that feed upon crayfish, aquatic invertebrates, fish, and frogs (Alsop 2001a and 2001b). Individuals of this family range in weight from 0.4 to 1.3 kg (Dunning 1984) (Table E11).

      Table E11
      Body Weights and Diets of Species of Threskiornithidae that Prey upon Aquatic Animals
      Species (scientific name) Body weight
      (kg)1
      Diet2
      White-faced ibis (Plegadis chihi) 0.43-0.81 crayfish, aquatic invertebrates, fish, frogs
      White ibis (Eudocimus albus) 0.59-1.28 not stated

      1Dunning 1984; 2Alsop 2001a and 2001b

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  • E.2 Detailed Conceptual Model

    A detailed version of the conceptual model of the aquatic ecosystem depicted in Figure I of the User's Guide, with specific birds identified, is provided in Figure E1.

    Aquatic food web. 7 trophic level boxes in water column. Arrows from lower to higher levels of the food web. Sediment at graphic bottom. Birds in boxes above the water column.Figure E1
    Detailed conceptual model depicting aquatic food web of KABAM.
    Arrows depict direction of trophic transfer of bioaccumulated pesticides from lower levels to higher levels of the food web.

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  • E.3 Determination of Daily Food Intake

    If the weight of a food item (i.e., aquatic trophic level) is less than that of the amount of food consumed by the bird in one day, then the food item is a reasonable assignment. In order to determine whether or not a particular trophic level is relevant to a bird, the daily food intake is estimated.

    The dry food intake per day (Fdry, kg/day) for a bird can be calculated according to Equation E1 (USEPA 1993). This value can be converted to represent food intake per day on a wet weight basis (Fwet, kg/day) by assuming that the diet of an organism is 75% water (Equation E2, see Appendix C for % water of aquatic organisms).

    Equation E1

    Fdry = 0.0582 * BW0.651

    Equation E2

    Fwet = Fdry / [1 - (% water of diet)]

    Of the bird families described above, body weights range 0.02-7.5 kg. The resulting wet food intakes per day for birds of concern for KABAM are provided in Table E12. This table presents food intake values per day for each species based on body weight. These wet food intakes can be used to assign appropriate aquatic animals to the default diets of these birds.

    Table E12
    Body Weights Representative of Birds that Consume Aquatic Animals and Corresponding Daily Dry and Wet Food Intakes
    Family or species Body weight range (kg) Dry Food Intake per day (kg) Wet Food Intake per day (kg)
    Sandpipers 0.02- 0.70 0.005-0.046 0.018-0.185
    ducks 0.30-2.00 0.027-0.091 0.106-0.366
    cranes 2.45-6.70 0.104-0.201 0.417-0.803
    belted kingfisher 0.13-0.22 0.015-0.022 0.062-0.087
    rails 0.07-0.49 0.010-0.037 0.041-0.146
    ibis 0.43-1.28 0.034-0.068 0.134-0.273
    grebes 0.22-1.82 0.022-0.086 0.087-0.344
    Double-breasted cormorant 1.8 0.085 0.341
    Bitterns, egrets, herons 0.08-2.90 0.011-0.116 0.045-0.466
    osprey 1.25-2.00 0.067-0.091 0.269-0.366
    Bald eagle 3.00 - 5.80 0.119-0.183 0.476-0.731
    white pelican 7.5 0.216 0.864

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  • E.4 Definition of Default Parameters to Represent Birds in KABAM

    Based on the species descriptions above, birds can be divided into three groups based on their diets. The three diets (Table E13) include:

    1. filter feeders, benthic invertebrates and fish
    2. benthic invertebrates and fish and
    3. fish.

    These three diets were used to define the default parameters representing birds in KABAM (Table E14), which are described below.

    Table E13
    Summary of Diets and Body Weights of Families of Birds Defined as Consuming Aquatic Animals
    Diet Family or species Body weight range (kg)
    Filter feeders, benthic invertebrates, fish Sandpipers 0.02- 0.70
    Ducks 0.30-2.00
    Cranes 2.45-6.70
    Benthic invertebrates and fish Belted kingfisher 0.13-0.22
    Rails 0.07-0.49
    Ibis 0.43-1.28
    Grebes 0.22-1.82
    Double-breasted cormorant 1.80
    Bitterns, egrets, herons 0.08-2.90
    Fish Osprey 1.25-2.00
    Bald eagle 3.00 - 5.80
    White pelican 7.50
    Table E14
    Default Body Weights and Diet Parameters for Use in KABAM to Represent Birds
    Bird # Bird Name Relevant Families/species Default weight (kg) Default diet
    1 Sandpipers Sandpipers, ducks, cranes 0.02
    • 33% benthic invertebrates
    • 33% filter feeders
    • 34% small fish
    2 Cranes Sandpipers, ducks, cranes 6.70
    • 33% benthic invertebrates
    • 33% filter feeders
    • 34% medium fish
    3 Rails Belted kingfisher, rails, ibis, grebes, double-breasted cormorant, bitterns, egrets, herons 0.07
    • 50% benthic invertebrates
    • 50% small fish
    4 Herons Belted kingfisher, rails, ibis, grebes, double-breasted cormorant, bitterns, egrets, herons 2.90
    • 50% benthic invertebrates
    • 50% medium fish
    5 Small Osprey Osprey, bald eagle, white pelican 1.25 100% medium fish
    6 White pelican Osprey, bald eagle, white pelican 7.50 100% large fish

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    • E.4.1. Birds Consuming Benthic Invertebrates, Filter Feeders, and Fish

      Because sandpipers, ducks, and cranes share similar diets (i.e., benthic invertebrates, filter feeders, and fish), they are considered as a group for defining input parameters for KABAM. Two of the default birds in KABAM (# 1 and 2) represent birds with a similar diet.

      Comparison of the daily wet food consumption for sandpipers (Table E12) to the weight of small and medium fish in KABAM (0.01 and 0.1 kg, respectively) indicates that not all of these species would be expected to consume medium-sized fish. Therefore, it is assumed that sandpipers consume small fish. All species of cranes are expected to be able to consume a medium-sized (0.1 kg) fish in one day. Therefore, it is assumed that the diet of cranes is composed of medium-sized fish. Since the relative proportion of benthic invertebrates, filter feeders and fish within the diets of these species is unknown, it is assumed that these prey items compose an equal share of the diet of these birds.

      The 1st default bird in KABAM has a diet of 33% benthic invertebrates, 33% filter feeders and 34% small fish. This bird is intended to represent the low end of birds that consume benthic invertebrates, filter feeders, and small fish. Therefore, the default body weight of 0.02 kg was selected because it is consistent with the lowest body weight of birds that have this diet (Table E13).

      The 2nd default bird in KABAM has a diet of 33% benthic invertebrates, 33% filter feeders, and 34% medium fish. This bird is intended to represent the high end of birds that consume benthic invertebrates, filter feeders, and medium-sized fish. Therefore, the default body weight of 6.7 kg was selected (Table E14).

      It should be noted that pesticide EECs and subsequent RQs for sandpipers, ducks, and cranes are bound by KABAM's default birds 1 and 2. RQs for these two default birds are intended to represent birds with similar size and feeding habits as sandpipers, ducks, and cranes. These EECs and RQs can be refined by the model user to represent a specific bird species by entering specific body weights of individual species of concern and the appropriate species composition of their diet.

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    • E.4.2. Birds Consuming Benthic Invertebrates and Fish

      Because belted kingfisher, rails, ibis, grebes, double-breasted cormorants, bitterns, egrets, and herons share similar diets (i.e., benthic invertebrates and fish), they are considered as a group for defining input parameters for KABAM. Two of the default birds in KABAM (# 3 and 4) represent birds with a similar diet.

      Comparison of the daily wet food consumption for small rails, small grebes, and the belted kingfisher (Table E12) to the weight of small and medium-sized fish in KABAM (0.01 and 0.1 kg, respectively) indicates that not all of these species would be expected to consume medium fish. Therefore, it is assumed that some of these species consume small fish. Species of rails, ibis, grebes, bitterns, egrets, herons and the double-breasted cormorant are expected to be able to consume a 0.1 kg fish per day. Therefore, it is assumed that the diet of these species is composed of medium-sized fish. Since the relative proportion of benthic invertebrates and fish within the diets of these species is unknown, it is assumed that these prey items compose an equal share of the diet of these birds.

      The 3rd default bird in KABAM has a diet of 50% benthic invertebrates and 50% small fish. This bird is intended to represent the low end of birds that consume benthic invertebrates and small-sized fish. Therefore, the default body weight of 0.07 kg was selected because it is consistent with the lowest body weight of birds that have this diet (Table E13).

      The 4th default bird in KABAM has a diet of 50% benthic invertebrates and 50% medium fish. This bird is intended to represent the high end of birds that consume benthic invertebrates and medium-sized fish. Therefore, the default body weight of 2.9 kg was selected (Table E14).

      It should be noted that pesticide EECs and subsequent RQs for belted kingfisher, rails, ibis, grebes, double-breasted cormorants, bitterns, egrets, and herons are bounded for KABAM's default birds 3 and 4. RQs for these two default birds are intended to represent birds with similar sizes and feeding habits. These EECs and RQs can be refined for specific bird species by entering specific body weights of individual species of concern and entering the appropriate diet.

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    • E.4.3. Birds Consuming Fish

      Because osprey, bald eagles, and white pelicans share similar diets (i.e., fish), they are considered as a group for defining input parameters for KABAM. Two of the default birds in KABAM (# 5 and 6) represent birds with a similar diet.

      Comparison of the daily wet food consumption for the lower end body weight (1.25 kg) of these birds to the weight of medium and large fish in KABAM (0.1 and 1.0 kg, respectively) indicates that the lower weight individuals of these bird species are able to consume medium fish, but unlikely to consume large fish. Therefore, it is assumed that the diet of default bird #5 (named osprey), can be represented by 100% medium-sized fish. Comparison of the daily wet food consumption (0.86 kg/day) for the higher end body weight (7.5 kg) of these birds to the weight of large fish in KABAM (1.0 kg) indicates that the higher weight individuals of these bird species are likely to consume large fish. Therefore, it is assumed that the diet of default bird #6 (named white pelican), can be represented by 100% large-sized fish.

      In order to bound EECs and RQs for these three birds, the lowest and highest body weights were selected to represent KABAM's default birds 5 and 6, respectively, in KABAM. These EECs and RQs can be refined for specific bird species by entering specific body weights of individual species of concern.

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