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Martins Creek
Section 04
Northampton County
Wild brown trout assessment
August 2010

On August 9 and 10 personnel from the Area 5 (Bushkill) Fisheries Management office conducted an electrofishing survey in Section 04 of Martins Creek in Northampton County to quantify the abundance of wild brown trout. Section 04 extends 1.90 miles from its confluence with the Delaware River upstream to a dam located approximately 0.4 miles upstream from where Township Road (T-651 - Old Franklin Hill Road) joins State Route 1015 (Main Street) north of the village of Martins Creek.

Martins Creek
Martins Creek downstream from State Route 611 Bridge Crossing

Two historically surveyed sites, totaling 631 meters or 21% of the section’s length, were surveyed. A total of 471 individual wild brown trout were captured during the survey. Their sizes ranged from 3 to 23 inches in length, with those of legal size (> 7 inch) and larger accounting for 83% of the total number of brown trout handled (Figure 1).

Figure 1. Length frequency distribution for brown trout captured at river mile 0.60 and 1.70 during the August 2010 survey of Martins Creek, Section 04.

Figure 1

Brown trout biomass was estimated to be 59.44 and 288.97 kg/ha at RM 0.60 and RM 1.70, respectively. These estimates resulted in an average biomass of 174.20 kg/ha for the section, which was more than four times the minimum biomass of 40.00 kg/ha for a Class A biomass designation (Figure 2).

Figure 2. Site biomass estimates and the Section 04 average for wild brown trout captured during the August 2010 survey.

Figure 2

Substantial variation between the two estimates was attributed to habitat differences influencing the amount of available cover for trout. For example, RM 1.70 had optimal habitats with fish cover consisting of several deep pools and desirable undercut banks throughout the reach electrofished. In contrast, RM 0.60 had suboptimal habitats consisting of noticeably shallower pools with less fish cover (i.e., boulders, undercut banks). In addition, a dam at the upstream end of the survey site at RM 1.70 created an exceptionally large plunge pool that contained many trout, including several greater than 20 inches. This dam functioned as a block for fish movement upstream while creating a favorable habitat that appeared to concentrate fish (Figure 3). The stream’s habitat at RM 1.70 was enhanced by the presence of the dam and demonstrates the holding potential when suitable habitat is abound throughout. Site RM 0.60 is more reflective of the overall stream habitat of the section, which is still quite good as indicated by the presence of a Class A wild brown trout population.

Figure 3. Three large brown trout handled during the survey.

Brown trout
Two brown trout

Historically the sampling sites at RM 0.60 and 1.70 had consistently supported similar densities of wild brown trout and when averaged have exceeded the Class A biomass standard (Figure 4). These estimates along with recent changes to the streams sectioning strategy have now afforded the opportunity to officially recognize and manage the lower portion of Martins Creek as a Class A wild trout water.

As a result of the 2010 and earlier surveys Martins Creek Section 04 will be proposed for adding to the statewide list of Class A waters.

Figure 4. Time series estimates for wild brown trout biomass recorded at river miles 0.6 and 1.7.

Figure 4

Of further interest to anglers was the catch of 20 smallmouth bass from 3 to 16 inches in length, nine hatchery rainbow trout from 9 to 12 inches, three hatchery brook trout from 10 to 13 inches, and one hatchery brown trout at 9 inches. For a list of other fish species present see Table 1.

Table 1. Other fish species present during the August 2010 survey of Martins Creek, Section 04.

Common name Scientific name
American Eel Anguilla rostrata
Blacknose Dace Rhinichthys atratulus
Fallfish Semotilus corporalis
Longnose Dace Rhinichthys cataractae
Pumpkinseed Lepomis gibbosus
Tessellated Darter Etheostoma olmstedi
White Sucker Catostomus commersonii
— Area 5 Fisheries Management Office

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