Welcome to Frank's Field Notes, a semi-regular look at what’s happening across the Prairie Pothole Region during spring migration and breeding season.

Part field journal, part migration report, and part window into duck country, Delta Waterfowl Chief Scientist and President Dr. Frank Rohwer offers firsthand observations from the field on ducks, geese, weather, habitat conditions, and the annual return north.

Flying ducks

Mixed Delta ducks

9/23/2026

Grey light, but many species. Can you get them all?

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slough pump

9/22/2026

American Bitterns are common at Delta and across the PPR.

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molt feather comparison

last tail feathers to replace

9/21/2026

Ducks hatched this summer carry notched tail feathers compared to non-notched tails.

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Avocet in winter and summer

Winter versus summer plumage

9/20/2026

I saw lots of Avocets on wetlands across Saskatchewan.

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first crane

9/19/2026

Research team had a great trip to Saskatchewan.

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Blue winged Teal females

Adult female BWT

9/18/2026

Adult females are about the last cohort to leave for the winter.

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Gray Partridge

Gray Partridge

9/17/2026

Hungarian Partridge – officially Gray Partridge – were introduced from Europe in the 1900s.

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sunrise

Duck steaks - great for the grill

9/16/2026

One of my favorite ways to eat duck is to grill both breast with the skin still attached to the breast muscles.

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juvenile coot

Juveniles are everywhere

9/15/2026

This is a juvenile coot, with light grey plumage.

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Spinner Decoys

spinning wing decoys - work better north

9/14/2026

Afton and Szymanski researched the effects of spinning wing decoys years ago – striking benefit up north; not in Louisiana.

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Crane Wing

Crane Wing

9/13/2026

Molt is a major energy expense for birds with big wings.

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Hard to be selective

9/12/2026

Bills and wings are the only easy ways to distinguish males and females.

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Coot

Lobed toes for better swimming

9/11/2026

Coots are in the rail family, but swim much more than other rails – hence the lobes on their toes.

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Marbled Godwit

Big shorebird

9/10/2026

Marbled Godwits are one of the largest shorebirds in North America.

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Mallard Hunt

Being an adult male is good

9/9/2026

We found a great pea field that held about 5,000 Mallards and Pintails.

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Bufflehead and blue winged teal

OOPS - small but not a teal

9/8/2026

Mistakes happen – that is a hen Bufflehead, not a Blue-winged teal.

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Bills

Bill Spots for Aging Female Ducks

9/7/2026

Another way to age some female dabblers is by the size of the bill spots.

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ducks and field peas

Peas - cocaine for ducks

9/6/2026

Mallards and Pintails are addicted to field peas.

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aging feathers

Distinguishing age classes

9/5/2026

An easy way to split age groups is by looking at tail feathers

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BTWE wings

Teal season opening soon - differentiating sexes

9/4/2026

Special teal season start soon in many states. All blue-wings are in basic (aka eclipse) plumage at this time of year.

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first hunt

Christmas in September

9/3/2026

Spent September 1 (Christmas) in Saskatchewan with Spaniel Spat – glorious.

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graphs

Bpop report out - not all bad news

9/2/2026

Cans and Scaup were both up 13% over last year.

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Blue winged teal with band

Fun banding video

9/1/2026

Charlee spliced together a one-minute video of Delta banding.

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Graph of banding effort

Delta Marsh banding

8/31/2026

Species totals for Banding effort.

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Nice sunset - fall is coming

8/30/2026

That isn’t the Missouri River, but we had a great sunset with much smaller flocks of resident Canada Geese.

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Late Brood

Very late brood

8/29/2026

Today I made an excursion up to southern Manitoba and southeastern Saskatchewan.

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Diving Tern

Plunge Dive Foraging

8/28/2026

We have both Common Terns and Forester’s Terns at Delta Marsh. They both plunge dive to catch small fish.

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Bufflehead, Lesser Scaup, Ring necked duck

British Columbia Breeding Population Numbers

8/27/2026

I just got a copy of the spring Breeding population survey for BC.

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Delta Banding Crews

Banders at Delta

8/26/2026

The Delta banding crew is mostly comprised of southern graduate students that are up north getting prairie and banding experience.

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Mallard band recovery map

Delta Banding going well

8/25/2026

Our banding crew at the Delta Marsh has well over 1,800 birds banded this month.

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Alaska map with Wigeon and Pintail

Fantastic flight in a Beaver

8/24/2026

I had a terrific flight in a 1950’s era de Havilland Beaver a couple hours out the Alaska Peninsula from King Salmon.

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Gadwall

California breeding ducks down

8/6/2026

California Game and Fish released their statewide spring breeding duck count this week.

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