Minnesota · Crow Wing County

Bertha Lake Fishing guide

Bertha Lake is a 337-acre lake in Crow Wing County, Minnesota, reaching 64 ft at its deepest point. Average water clarity runs about 15.6 ft. The Minnesota DNR has surveyed the lake 11 times, most recently in 2024, with walleye, largemouth bass, smallmouth bass and northern pike in the nets.

Open the live map → Survey data

Depth to 64 ft · top 5 summer marks

Surface337 ac

Max depth64 ft

Clarity15.6 ft

Littoral42%

Surveyed2024

How to fish Bertha Lake through the year

Walleye

Spring: Walleye are shallow, on and just off the spawning flats and the first green weeds. At 15.6 ft of clarity, fish them deeper and lighter than usual.
Early summer: Walleye are setting up on the outside weed edge, points and shallow structure.
Summer: Walleye are working the weed edge, points and any wind-blown structure. On a lake that drops to 64 ft, check the deep edge of that structure too.
Fall: Walleye are packing onto the sharpest breaks and points as the water cools, in big schools with short windows.

Northern pike

Spring: Pike are in the shallow bays and along new weed growth. At 15.6 ft of clarity, fish them deeper and lighter than usual.
Early summer: Pike are on the outside weed edge and points.
Summer: Pike are on the deep weed edge and points near the coolest water they can find. On a lake that drops to 64 ft, check the deep edge of that structure too.
Fall: Pike are on the last green weeds and the breaks beside them, feeding heavily as the water drops.

Season patterns for each species. Open the live map for today's wind, light and water temp.

Size history

Biggest fish by survey year

Survey year	Walleye	Northern pike	Largemouth bass
2024	28"	31"	14"
2018	29"	35"	17"
2011	30"	35"	16"
2005	28"	37"	13"
2000	31"	38"	15"
1995	30"	32"	7"

Longest fish measured by DNR survey crews in each year's nets. Survey gear samples the population, so the lake usually holds larger fish than any survey measured.

Suggested tackle

What to bring

Top presentations for this lake's structure and clarity:

Walleye · Live bait

Live-Bait (Lindy) Rig + Leech/Crawler

jumbo leech or half a nightcrawler

8–35 ftslow

Shop octopus hooks →

Walleye · Trolling

Leadcore Line + Crankbaits

4–5" mid-diving crankbait behind a long leadcore run

15–45 fttrolling

Shop deep-diving crankbaits →

Northern pike · Soft plastics

Paddletail Swimbait on Jighead

4–5" paddletail swimbait on a ball-head swimbait jighead

3–25 ftmoderate

Shop paddletail swimbaits →

Northern pike · Muskie & pike

Soft Rubber (Bull Dawg / Medusa)

10" soft rubber body bait

3–25 ftslow

Shop musky rubber →

Largemouth bass · Soft plastics

Texas-Rigged Worm

7" ribbon-tail or straight-tail plastic worm

1–25 ftdead slow

Shop plastic worms →

Largemouth bass · Soft plastics

Free Rig

Creature bait or magnum finesse worm

8–30 ftdead slowweedless

Shop creature baits →

Full setups, including hooks, weights and line, are on the live map. As an Amazon Associate I earn from qualifying purchases.

MN DNR · in their words

From the 2024 survey

Bertha Lake is a 334 acre lake and is part of the Whitefish Chain located in northern Crow Wing County. The maximum depth is 64 feet, with 43% of the lake 15' or less.

One thing unique to Bertha, compared to other lakes in the Brainerd Area, is that while the numbers of Walleye and Northern Pike may not be high, large fish are common. The presence of Tullibee (Cisco) likely contributes to the quality size of large predators. Numbers of Tullibee (Cisco) were a little lower this survey (6.2/net) than the previous survey (14.8/net), however, the catch has been as high as 31.2/net. Walleyes are not stocked into Bertha but are stocked annually as fry and every other year as fingerlings into the Whitefish Chain; Walleyes can move throughout the chain and into Bertha. Walleye numbers were average at 1.4/net, but as mentioned previously, they were nice size. They had an average length of 24.4", with fish up to 28.4" present. It was a similar story with Northern Pike, with 29% of sampled pike 26" or larger. Catch rates from 2024 (8.6/net) were comparable to the previous survey (7.9/net).

Read the full DNR narrative

Largemouth Bass electrofishing was conducted at various stations across the Whitefish Chain of Lakes, resulting in a combined catch rate of 44.9/hour. Average length was 13.1" and 65% were over 12", with fish up to 19.2" sampled. Three Smallmouth Bass were also netted while electrofishing and all of them were over 16".

Black Crappies were sampled in low numbers in both gill nets (0.3/net) and trap nets (0.2/net). Fish were around the size that anglers begin to harvest them, with 80% of the fish measuring 8" or larger, but the largest fish was only 9.4". Bluegills were sampled in average numbers at 26.0/trap net. With an average length of 5.2" and only 8% of the fish measuring 7" or larger, anglers may want to look elsewhere in the chain to target panfish. A special regulation on the Whitefish Chain reduces the daily limit of Sunfish and Crappie to 5 of each.

Bertha Lake is designated as AIS (aquatic invasive species) infested waters because of zebra mussels. Lake users are required to inspect and remove any aquatic plants and animals from their watercraft and trailers as well as pull the plug and drain all water from the watercraft, including bilges, livewells and baitwells.

Narrative text from the Minnesota DNR lake survey.

Recent reports

Bertha Lake fishing reports

Recent reports on Bertha Lake from guides, tournaments and regular anglers. Anything posted in the last two weeks also bumps the matching spots on the live map, so you'll see a "matches a recent report" tag on them.

Open the live map → Fished it lately? Write a report

Crow Wing County reports

Public water access

Getting on the water

Public access: Via channel from Whitefish.
Public access: Via channel from Clamshell Lake.

DNR bathymetry

Bertha Lake depth map

Bertha Lake depth contour map, Crow Wing County, Minnesota — Depth contours to 64 ft from Minnesota DNR bathymetry, free to save or print. The live map adds ranked spots and conditions on the same contours.

Within 30 miles

Nearby lakes

Clamshell Lake · 211 ac · 1.3 mi
Grass Lake · 46 ac · 1.5 mi
Clear Lake · 226 ac · 1.6 mi
Lower Hay Lake · 700 ac · 1.7 mi
Whitefish Lake · 7,714 ac · 2.3 mi
Strawberry Lake · 20 ac · 2.4 mi
Kimball Lake · 190 ac · 2.6 mi
Upper Hay Lake · 596 ac · 2.6 mi

Quick answers

Frequently asked questions

How deep is Bertha Lake?

Bertha Lake reaches 64 ft at its deepest point; about 42% of the lake is littoral (15 ft or shallower).

How big is Bertha Lake?

Bertha Lake covers 337 acres with about 3.9 miles of shoreline.

How clear is the water in Bertha Lake?

DNR Secchi readings on Bertha Lake average 15.6 ft of visibility, clear water for a Minnesota lake.

What fish are in Bertha Lake?

Minnesota DNR surveys (most recently 2024) record walleye, largemouth bass, smallmouth bass, northern pike, bluegill, crappie, yellow perch, rock bass.

Is Bertha Lake stocked?

No stocking is on record for Bertha Lake in the DNR's stocking database.

Does Bertha Lake have a public access?

Yes. Bertha Lake has 2 public access sites, including a Public access (Via channel from Whitefish.).

How big do walleye get in Bertha Lake?

The biggest walleye measured in recent DNR surveys taped 28"; the size-history table on this page tracks the biggest fish in each survey back to 1995.

When was Bertha Lake last surveyed?

The Minnesota DNR last surveyed Bertha Lake in 2024, the most recent of 11 surveys on record.

Page updated September 22, 2026.

The live map adds today's conditions and ranked spots for Bertha Lake, plus a trip plan you can share:

Open Bertha Lake on the live map → Fished it lately? Write a report