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Roseate Tern (Sterna Dougallii)

Appendix A


Biological Suitability Criteria (BSC) developed by the US Roseate Tern Recovery Team for choosing colony restoration sites.
1) If known, distance from potential colony site to nearest regularly-used important foraging area<5 km5-15 km>15 km
2a) Presence of known ‘mainland-based’ predators (Great Horned Owl, corvids, coyote, fox, mink, feral cats, rats) ORnoneat least 1 species reported2 or more species reported
2b) Distance of potential colony site to mainland or to closest large (>50 ha) island that could serve as a source of important ‘mainland-based’ predators>5 km1-5 km<1 km
3a) Historical or recent occurrence of predation by Black-crowned Night-Herons ORnone reported by BCNHinfrequent predation by BCNHfrequent or ‘heavy’ predation
3b) Distance of potential tern colony site to colony site of Black-crowned Night-Herons>20 km5-20 km<5 km
4a) Historical or recent occurrence of predation by large gulls such as Great Black-backed or Herring Gulls ORnone reported by gullsinfrequent predation by gullsfrequent or ‘heavy’ predation
4b) Distance of potential tern colony site to colony site of Great Black-backed or Herring Gulls>10 km3-10 km<3 km
5a) If known, most recent 5-yr mean productivity for peak-nesting Roseate Terns (fledglings/pair) OR>1.21.0-1.2<1.0
5b) Subjective evaluation of historical use and productivity by Roseate Terns (or Common Terns)regular use & high productivityinfrequent use and/or unknown productivityno use or use & low productivity
6) Island Size>2 ha1-2 ha<1 ha
7) Susceptibility to floodinglowmediumhigh
8) Long-term stabilityhighmediumlow
9) Vegetation/substrateaappropriateintermediateunsuitable

a Vegetation/substrate suitability to be based on professional judgment:
                appropriate = mix of semi-open substrate with patches of cover
                intermediate = vegetation somewhat too dense for Common Terns: no trees
                unsuitable = too open for Roseate Terns or too dense for Common Terns

Logistic Practicality Criteria (LPC) developed by the USRoseate Tern Recovery Team for choosing colony restoration sites.
1) Ownership/Management Commitment (Supportive attitude of current owner towards tern management)Government wildlife agency or conservation organizationOther government agencyPrivately owned or managed
2) Ease of rescue/evacuation<5 km to marina5-10 km to marina>10 km to marina
3) Usable buildings/facilities for overnight stays for wardensExisting buildings can be used by wardensCamping possibleDay visits only due to no area for camping
4) Accessibility for boat landingHarbor/dockSheltered landingNo sheltered landing
5) Number of gulls to be removed<50 pairs50-500 pairs>500 pairs
6) Size of area to be managed<5 ha5-15 ha>15 ha
7) Public visit/disturbance potentialLowMediumHigh
8) Other potential concerns such as compatibility of management for terns with existing island use/activities?NoneMinor concernsMajor concerns
9) Public education potentialHighMediumLow