Facts about Lesser Scaup

1. 12

   Wintering Lesser Scaup are closely related to Greater Scaup but can be distinguished by the peaked, rather than rounded, shape of their head crown.

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2. 11

   In spring migration, Lesser Scaup males exhibit rapid color changes in their head plumage, shifting from dark purple to glossy black within weeks as testosterone levels surge before reaching breeding grounds.

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3. 10

   Courtship displays of Lesser Scaup males involve synchronized head-throwing motions performed in rapid succession, with some males executing up to 15 head tosses per minute to attract females during spring migration.

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4. 09

   The distinctive yellow eye of Lesser Scaup males darkens to nearly black during courtship displays, serving as a visual signal to competing males and receptive females on breeding grounds.

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5. 08

   A Lesser Scaup's bill contains specialized lamellae structures with roughly 100 fine tooth-like projections per side that filter food particles from water while diving.

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6. 07

   Approximately 90% of the global Lesser Scaup population winters in coastal bays and estuaries from the Gulf Coast to the Pacific, concentrating their annual cycle in just three major regions.

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7. 06

   North American Lesser Scaup populations have declined by approximately 56% since the 1970s, primarily due to habitat loss in prairie pothole breeding regions.

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8. 05

   Lesser Scaup females exhibit philopatry, returning to the same prairie breeding sites year after year, with some individuals showing site fidelity for over 10 consecutive seasons.

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9. 04

   Female Lesser Scaup lay clutches of 8 to 14 eggs in prairie wetlands of North America, with incubation lasting approximately 24 to 28 days.

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10. 03

    Flocks of Lesser Scaup can exceed 500,000 individuals on Lake Michigan during peak winter migration, making it a critical continental staging area for the species.

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11. 02

    Male Lesser Scaup can produce over 1,000 sperm per second during breeding season, enabling rapid fertilization of multiple females across their wintering grounds.

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12. 01

    During winter, Lesser Scaup can dive to depths exceeding 40 feet to forage for aquatic invertebrates and plant matter on lake bottoms.

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