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.

close up

9/30/2026

Great Blue Herons are still at Delta Marsh working on the small fish.

Not what we want to see

9/29/2026

I have no huge problem with drain tile as long as they don’t drain wetlands.

Learning to forage can be hard

9/28/2026

In the bird world – ducks included – young birds almost always have lower survival than adults.

Winter vs. Summer - amazing

9/27/2026

The difference between winter and summer plumage in Long-tailed Ducks is simply amazing.

Beautiful birds in breeding plumage

9/26/2026

Like many duck hunters, I have never seen Long-tailed Ducks (aka oldsquaws) in their breeding plumage.

Learning or just foraging

9/25/2026

Female waterfowl home; males do not.

1/2 & 1/2

9/24/2026

Nice mix of 4 BWT and 4 GWT

Mixed Delta ducks

9/23/2026

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

slough pump

9/22/2026

American Bitterns are common at Delta and across the PPR.

last tail feathers to replace

9/21/2026

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

Winter versus summer plumage

9/20/2026

I saw lots of Avocets on wetlands across Saskatchewan.

first crane

9/19/2026

Research team had a great trip to Saskatchewan.

Adult female BWT

9/18/2026

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

Gray Partridge

9/17/2026

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

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.

Juveniles are everywhere

9/15/2026

This is a juvenile coot, with light grey plumage.

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.

Crane Wing

9/13/2026

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

Hard to be selective

9/12/2026

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

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.

Big shorebird

9/10/2026

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

Being an adult male is good

9/9/2026

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

OOPS - small but not a teal

9/8/2026

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

Bill Spots for Aging Female Ducks

9/7/2026

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

Peas - cocaine for ducks

9/6/2026

Mallards and Pintails are addicted to field peas.

Distinguishing age classes

9/5/2026

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

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.

Christmas in September

9/3/2026

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

Bpop report out - not all bad news

9/2/2026

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

Fun banding video

9/1/2026

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

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.

California breeding ducks down

8/6/2026

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