www.fishhaw electronics.com 5
The Search for the Right Water Temperature
Every body of water has temperature changes from the top to the bottom. There
are layers of water where the temperature will be significantly different. These are
differences are referred to as “temperature breaks” or the “thermocline.” Often
fish will travel along the thermocline or temperature break, and finding these ar-
eas is key to finding fish
Each species of fish lives in a preferred water temperature range. The chart be-
low shows the preferred water temperature range for the most popular freshwater
game fish and baitfish species in Fa enheit.
Preferred Water Temperature Ranges
(shown in Fahrenheit)
Species Lower Limit Optimum Upper Limit
Brown Trout 44 52 75
Chinook Salmon 40 44 60
Coho Salmon 44 54 60
Crappie 60 70 75
Kokanee 52
Lake Trout 40 42 55
Largemouth Bass 50 70 80
Atlantic Salmon 45 50 60
Rainbow Trout 44 54 63
Smallmouth Bass 50 65 73
Steelhead 42 45 62
Walleye 50 67 76
Alewife 48 54 72
Cisco 53
Emerald Shiner 61
Gizzard Shad 69
Rainbow Smelt 43 50 57
Spottail Shiner 54
Fish suspend in the water column by water temperature. Using your Fish Hawk will
allow you to find them. With the Fish Hawk you can create a temperature profile of
the water column by lowering the probe close to the bottom and observing the water
temperature as you slowly raise the probe to the surface. This will allow you to find the
correct water temperature for the species you are targeting.
Fish Hawk X4/X4D Components
The Fish Hawk can be purchased as a complete system or as an Upgrade Kit for
previous models. Replacement Probes are available separately if needed. Depending
on which configuration you have purchased, your package will include the following:
Fish Hawk System
• Transducer with 30’ cable
• Transducer mounting kit
• LCD display
• Power cord for LCD display
• LCD display stand
• Fish Hawk Probe
• Breakaway cannonball wire safety lead
• Protective rubber probe bumper
• This Owner’s Manual
Fish Hawk Upgrade Kit
• LCD display
• LCD display stand
• Fish Hawk Probe
• Breakaway cannonball wire safety lead
• Protective rubber probe bumper
• This Owner’s Manual
Fish Hawk Probe
• Fish Hawk Probe
• Breakaway cannonball wire safety lead
• Protective rubber probe bumper
• This Owner’s Manual
How the Fish Hawk Operates
The Fish Hawk Probe is fastened to the downrigger
cable just above the downrigger ball and has sensors that
constantly monitor water temperature and speed as it
travels through the water. The probe sends a sonar signal
with that information to the Transducer mounted on the
back of the boat. The Transducer, which is hooked up to
the LCD display, sends the data from the Probe and the
water’s surface to the liquid crystal display (LCD) mount-
ed in the boat.
As the water temperature, speed or depth (model X4D
only) changes, the LCD updates to reflect the new infor-
mation. To compensate for wave action, speed is calculated
over a 20-second period. The probe operates at depths
from 1 to 300 feet.
X4 Digital Display
Transducer
Transmitter
Downrigger
Ball
Downrigger
Line
Temperature
Sensors
Speed
Sensor
Break-Away
Lead
Probe
