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.

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.

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.

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.

Delta Banding going well

8/25/2026

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

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.

Tundra swans in abundance

8/23/2026

Tundra Swans are abundant here on the Alaska Peninsula.

Tree Swallows at Delta Marsh

8/22/2026

Thousands of Tree Swallows come to Delta in the late summer to molt where there are millions of midges.

Those wings are expensive

8/21/2026

Growing feathers requires substantial amounts of proteins with scarce amino acids.

Not long on the wing

8/20/2026

This young female Shoveler has probably been on the wing for less than three weeks.

Different migration schedules for the sexes

8/18/2026

Male ducks don’t do much parental care, so they molt earlier than females and are ready to migrate south earlier than females.

Several large broods at the MERP cells

8/18/2026

Some broods look like they lost no ducklings from the time of hatch.

Error yesterday - 15 bird bag limit

8/17/2026

Special seasons designed to reduce populations typically have liberal limits.

Opening morning

8/16/2026

Canada Geese were shot out of North Dakota, but rapid recovery started in the 1990’s.

Another great figure by Todd Arnold

8/15/2026

Blue-winged teal have a “faster” life cycle than Pintails or Mallards.

More great stuff from Delta Science Forum

8/14/2026

Reproduction drives duck numbers FAR more than survival or other factors.

Molt status matters - at least we think it does

8/12/2026

The photo shows the three options for wing molt

Delta Science Forum - cool new results

8/11/2026

Day 1 of the Delta Science Forum is in the bag.

The food for half the birds at Delta Marsh

8/10/2026

Males fly in huge groups that the girls briefly join, get a boy, mate, and lay eggs.

Pintail males are lecherous

8/9/2026

Forced extra-pair copulation is an even more prevalent male reproductive tactic in Pintails.

Great picture - but most duck hunters would fail t...

8/8/2026

The top, middle male is a hybrid between a Scaup and a Ring-necked Duck

Turkeys nest late

8/7/2026

Mixed age turkey broods are common in North Dakota.

California breeding ducks down

8/6/2026

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

Marbled Godwit

8/5/2026

Marbled Godwits stay in the prairies to nest in grassland habitats.

Smallest grebe in PPR

8/4/2026

Pied-bills may be slightly smaller than all others in the PPR, but they are surprisingly aggressive.

Banding is off and running

8/3/2026

Delta started a banding station several years ago.

Reprise on White-faced Ibis

8/2/2026

Fun info – the first ND breeding record was 1999 at Lake Alice NWR by our own Joel Brice.

Good news - brood index up a lot

8/1/2026

Results from the July wetlands and brood counts conducted by NDGF staff were just released.

White-faced Ibis expanding north

7/31/2026

White-faced Ibis nest in colonies of dozens to hundreds of birds.

Beneficiaries of waterfowl dollars

7/30/2026

Upland Sandpipers have greatly benefited from duck dollars.

Day three of eiders

7/29/2026

King Eiders are good looking birds with a circumpolar breeding range.

Beautiful eiders

7/28/2026

Steller’s Eiders are the smallest of the 4 eiders.