Family/species Avg. r Avg Wt Wt per surface area Max. wt for no penetration
(µm) (kg) (kg/m2) (kg/m2)
Penguins 32 2.84 63.6 – 78.8 95.3 – 98.4
Ducks/geese 30 1.40 32.5 – 43.3 45.0 – 58.3
Black-backed Gull 25 0.66 27.0 39.0 – 47.5
Herons 25 1.48 38.3 – 48.0 35.2 – 48.0