Rathbun Lake

Rathbun Lake

Size
13,920ac
Boat Launch
Yes
Carry-in Launch
No
Toilet
No
Boat Dock
No
Species in Rathbun Lake
Walleye
Walleye
Crappie
Crappie
Largemouth bass
Largemouth bass
Bluegill
Bluegill
Striped Bass
Striped Bass
Perch
Perch
Northern pike
Northern pike
Channel catfish
Channel catfish
Flathead catfish
Flathead catfish
White bass
White bass

Overview

Iowa's largest lake features walleye, catfish and crappie. Weeds and wood provide the cover for largemouth and white bass. Fluctuating water levels challenge any angler.

Rathbun Lake Map

Fishing Regulations

Special Fishing Regulations: This lake has special fishing regulations that differ from statewide or border water regulations for those species identified below and take precedence. Regulations listed below are currently in place. Visit the fishing regulations page for links to upcoming regulations for specific lakes.

Special Species Regulations

  • Walleye: Continuous: Daily Bag Limit: combined walleye, sauger and saugeye; 5 fish. Possession Limit: combined walleye, sauger and saugeye; 10 fish. Length Limit: 15-inch minimum length limit.

Features

Rathbun lake is situated just southeast of De Moines, Iowa close to the state line with Missouri. The lake was constructed in 1969 to aid in flood control for the Chariton River basin. Nearly 21,000 acres of land surrounds the lake, with nearly 16,000 of those acres leased to the Iowa Department of Natural Resources for wildlife management. Rathbun Lake is the largest lake within the state of Iowa. Most of the lake (and its floodplain) is managed primarily for waterfowl. From September 15 to December 15th nobody is permitted to enter designated waterfowl areas. The two restricted areas are shown on the map. Buoys and signs mark these areas on the lake during this period. Due to shallow areas, submerged trees and other structures lying just below the surface, all waters west of the Highway 142 bridge are considered hazardous boating areas. Summer boat traffic is generally moderate, except for heavy use on weekends and holidays.

Forage

Gizzard shad are abundant in the lake and serve as the primary forage base. Most of the gizzard shad are small enough to provide forage for most game species. Later in the season, some of the population can grow too large to be consumed. Juvenile crappie are utilized by larger species as well. At times, midgeflies and larvae supplement fish diets.

Seasonal Movements

Most walleye, white bass and catfish spawn within the lake instead of moving to inlet areas. However, in spring, the Iowa DNR nets walleye near the dam for spawning stock.

Weather

Current Weather Icon
75°Feels like 75°
High Temperature83°
Low Temperature63°
Sunrise
6:07 AM
Sunset
8:29 PM
Wind Direction
13 mph
South
Precipitation
0 in
Rain
Pressure
29.77 inHg
Falling
Mostly Cloudy with Chance of Storms
FridayFr
83° / 63°
Mostly Cloudy with Showers
SaturdaySa
78° / 63°
Mostly Sunny
SundaySu
82° / 61°
Sunny
MondayMo
84° / 64°
Mostly Sunny
TuesdayTu
87° / 66°
Partly Cloudy with Isolated Storms
WednesdayWe
83° / 68°

Moon Phase

waning gibbous
July 31, 2026
96% Illumination
waning gibbous, getting dimmer
Moon Rise and Set
Moon Rise 9:38 PM
Moon Set 8:05 AM
Moon Overhead Underfoot
Overhead 2:36 AM
Underfoot 2:57 PM
waning gibbous
FridayFr07/31
waning gibbous
SaturdaySa08/01
waning gibbous
SundaySu08/02
waning gibbous
MondayMo08/03
waning gibbous
TuesdayTu08/04
waning gibbous
WednesdayWe08/05
waning crescent
ThursdayTh08/06
Waterbody poster background

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Top Fish Species

Walleye
Walleye
8-26 in
Length Range
17 in
Length Range
2025
Surveyed
Abundance (CPUE)
Understanding Abundance

Abundance ratings are based on Catch Per Unit Effort (CPUE) measurements conducted by the MN DNR, and represent a snapshot of a species population at a given point in time

Source: Minnesota Department of Natural Resources. Survey cadence may vary by state and water body.
Species Lengths