Fish Attraction Structure Habitat Improvement Project:

2009 Monitoring Report

Niagara Power Project (FERC No. 2216)

June 2010

PREPARED BY:

 

Kleinschmidt Associates AND

Riveredge Associates

 

Prepared For:

 

New York Power Authority

©Copyright 2010.  New York Power Authority. All Rights Reserved


Table of Contents

1.0        Introduction.. 1

2.0        Objective. 1

3.0        Methods. 1

4.0        Results. 4

4.1        Physical Condition.. 4

4.2        Structure Utilization.. 6

5.0        Discussion.. 8

LIST OF FIGURES

Figure 1.  Location Shallow and Deep Water Fish Attraction Structures. 3

Figure 2.  Representative View of Substrate Taken at the Stone/Log Groin Structure. 6

Figure 3.  Smallmouth Bass Observed at the Stone/Log Groin Structure. 7

LIST OF TABLES

Table 1.  Fish Attraction Structures Monitored in 2009. 2

Table 2.  Summary of 2009 Monitoring Results. 5

 APPENDICES

APPENDIX A              2009 FIELD DATA COLLECTION FORMS

 


1.0       Introduction

The New York Power Authority's (NYPA) Niagara Power Project (Project) is licensed by the Federal Energy Regulatory Commission (FERC).  As part of the relicensing process, NYPA, state and federal resource agencies, local governments, nongovernmental organizations, and other stakeholders signed a Comprehensive Relicensing Settlement Agreement that requires NYPA to develop several Habitat Improvement Projects (HIPs) in the vicinity of Project lands and waters. 

One of these HIPs involves the construction and monitoring of fish attraction structures in the Upper Niagara River to provide large-object cover in new areas where fish of various sizes can feed, rest, and seek shelter.  In October 2008, NYPA constructed four fish attraction structures in the upper river using a barge at four locations.  Each consisted of a different design.  One shallow-water structure used a stone-and-log groin design while three deep-water structures used a boulder field, rock-wing saddleback, or rock slope design. 

The following sections of this report provide the September 2009 monitoring results of the structures, which was conducted one year after their installation.

2.0       Objective

Monitoring requirements for this HIP were outlined in the HIPs Report (Kleinschmidt Associates and Riveredge Associates, 2005).  Specifically, the monitoring objective is to gather and provide data to determine if the fish attraction structures are maintaining their structural integrity.  An ancillary objective for NYPA is to qualitatively evaluate structure use by fish.  Monitoring is scheduled to be conducted once per year in years 1, 4, 7, and 10, following construction; 2009 represents the first post-construction monitoring event.

3.0       Methods

Monitoring was conducted according to the Fish Attraction Structure Monitoring Plan (Kleinschmidt Associates, 2009). As such, monitoring was performed on September 23-24, 2009 by SCUBA divers who visually inspected the structures and conducted qualitative surveys at each of the four installation locations.  Survey dives took approximately 20 to 30 minutes each at each location.

During each survey, divers from Riveredge Associates and NYPA visually observed the physical condition of the structures to characterize their structural integrity.  Additional ancillary observations included presence or absence of fish, species observed and their relative abundance (e.g., 0, 1-10, 11-20, 21-50, 51-100, >100), how the habitat changes over time (e.g., sedimentation around the structures, zebra mussels clogging the interstitial spaces between the boulders, etc.), and other pertinent observations.  An Aqua-Vu camera linked to a digital video recorder and flat panel monitor was used to provide real-time video images to observers on the dive support boat, as well as to document condition of the structures and any observed use by fish.  Underwater still photos were also taken.  A data sheet was completed by the divers and boat observers immediately following each survey dive (Appendix A).

Monitoring occurred at the four fish attraction structures constructed at the locations shown in Figure 1 and listed in Table 1.

Table 1.  Fish Attraction Structures Monitored in 2009

 

Structure Coordinates

North American Datum of 1983 (NAD83)

Shallow Water (Gratwick Park)

Latitude

Longitude

Stone and Log Groin

43º 02' 55.0" N

78º 53' 38.0" W

 

 

 

Deep Water Locations

 

 

Boulder Field

43º 00' 21.6" N

78º 55' 40.9" W

Rock Wing “Saddleback”

42º 59' 24.0" N

78º 56' 30.0" W

Rock Slope

42º 57' 54.0" N

78º 56' 00.0" W

 


 Figure 1.  Location Shallow and Deep Water Fish Attraction Structures

FIGURE 1.  LOCATION SHALLOW AND DEEP WATER FISH ATTRACTION STRUCTURES

4.0       Results

Each fish attraction structure was visited over the course of two days in late September 2009.  Observations were recorded on the field data sheets included in Appendix A, and are summarized in Table 2.  Weather during the monitoring activities ranged from clear to cloudy, with an average water temperature of 20.3°C.  The average time of observation at each structure location was 21.5 minutes, with observation times ranging from 19 to 24 minutes.  Visibility was best on the first day of observation, allowing divers to see 6 to 10 feet at the Rock Slope structure at Motor Island.  Visibility at the remaining sites was somewhat lower on September 24th, only allowing divers to see distances less than 5 feet. 

4.1     Physical Condition

Generally all of the sites were in good condition with none of the structures experiencing noticeable shifting of the rock used in construction.  Where exposed to the current, the rocks were clean, but in sheltered areas the rocks were typically partially coated with silt and fine sediment, which was expected (Figure 2).  Embeddedness (the degree to which small particles fill in the spaces around larger rocks), was higher at the Stone and Log Groin structure, where sand and zebra mussel shells had accumulated in the voids around the larger rocks.  Three of the structures provided beneficial velocity breaks, as indicated by the decreased “flow through” observations, which can be used by fish for resting or ambush feeding behaviors.  At the Rock Wing, substantial sediment accumulation occurred in the existing “saddle” area, where a long, low ridge comprised of shells, sand and gravel has developed, extending between the two larger piles of rock at the structure’s ends.  In the Boulder Field, minor undercutting was observed around the upstream and lateral base of many of the boulders; material was subsequently deposited downstream of each boulder.

In general, logs used within the structures appeared to be in good condition with little to no damage from decomposition or shifting observed.  However, one log at the Stone/Log Groin structure, which had originally been cabled in place and partially covered with rock, had been shifted several yards downstream and off of the structure, possibly due to ice.  Although the rock holding the log has shifted, the cabling attached to the log appeared to be intact. 

Table 2.  Summary of 2009 Monitoring Results.

Observation

Attraction Structure

Rock Slope

Rock Wing

Boulder Field

Stone/Log Groin

Location

Motor Island

Upstream S. Grand Island Bridge

Downstream S. Grand Island Bridge

Gratwick Park

Date

9/23/2009

9/24/2009

9/24/2009

9/24/2009

Time Started

15:40

09:15

10:50

12:30

Length of Observation (min)

20

24

19

23

Weather

Clear

Cloudy

Cloudy

Cloudy

Water Temp (º C )

21

20.1

20.1

20.1

Visibility (Ft)

6 to 10

<5

<5

<5

Method

Divers

Divers

Divers

Divers

Structure Condition

No change to structure

Low ridge partially filled in; also upstream pile is gathering sediment

Sediment accumulation downstream; lots of zebra mussel shells

Ice may have moved one log off structure

Embeddedness

Coating of silt on everything

Saddle has partially filled in and now low ridge of sediment

Some undercutting in front of boulders

Debris/cans abundant in spaces between rocks, and downstream

Boulder Shift

None

None

None

None

Logs

Good Condition

Good condition

Good condition

One log moved

Fouling

Algae

Debris, trash

Algae

Debris

Flow Through

(relative to upstream/ downstream conditions)

Uniform (Slow)

Decreased

Decreased

Decreased

Fish Present

Yes

Yes

Yes

Yes

Smallmouth Bass (Adult)

11 to 20

51 to 100

21 to 50

11 to 20

Smallmouth Bass (Juvenile)

1 to 10

51 to 100

11 to 20

11 to 20

Gobies (Juvenile)

51 to 100

11 to 20

1 to 10

11 to 20

Comments

Juvenile smallmouth bass down in structure; several adult smallmouth bass holding above structure

Lots of fish!; vegetation growing in places along downstream end; structure breaking current as designed

Sediment accumulation downstream from each boulder

Wild celery establishing around edges of structure

Fouling of the structures was primarily a result of algal build up or debris (small woody debris, as well as aluminum beverage cans and plastic trash).  Wild celery, a type of submerged aquatic vegetation that provides valuable habitat, was observed growing around the edges of the Rock Wing and Stone/Log structures.

Distinct velocity breaks were observed at most structures, particularly at the Rock Wing where currents went from several feet per second on the upstream side to near-zero in the lee, and adult smallmouth bass were observed holding in and foraging from these areas.  The Rock Slope was the only site where a velocity decrease was not observed - current around the structure remained uniformly slow relative to upstream and downstream conditions.  

Figure 2.  Representative View of Substrate Taken at the Stone/Log Groin Structure

FIGURE 2.  REPRESENTATIVE VIEW OF SUBSTRATE TAKEN AT THE STONE/LOG GROIN STRUCTURE

4.2     Structure Utilization

Fish, primarily smallmouth bass and round gobies, were observed at all four structures at various densities and age classes (Figure 3).  Smallmouth bass were the predominant species observed at all structures with the exception of the Rock Slope, where more gobies were observed than smallmouth bass.  Juvenile smallmouth bass were observed using the cover provided by the spaces between the rocks at the structures.  Adult smallmouth bass were also observed using the logs at the structures as cover.  The Rock Wing structure appeared to have the largest quantities of smallmouth bass.  Gobies, an invasive species, were prevalent at the Rock Slope, and to a lesser degree in the undercut areas beneath the rocks in the Boulder Field.  Live zebra mussels, another invasive species, did not appear to be widespread; however, empty shells were abundant in gravely areas, particularly at the Rock Wing and Boulder Field structures.

Figure 3.  Smallmouth Bass Observed at the Stone/Log Groin Structure

FIGURE 3.  SMALLMOUTH BASS OBSERVED AT THE STONE/LOG GROIN STRUCTURE

5.0       Discussion

Based on the results of the 2009 monitoring effort, the fish attraction structures appear to be in good condition and are working as designed, providing good large-object cover for fish in the Niagara River.  With one minor exception, the physical integrity of the structures was not noticeably affected by shifting of boulders or logs within the structures.  The only shifting noted was at the Stone/Log Groin structure, where ice may have moved a single log from its original location.  This log is still present, but has been moved several yards downstream, off the top of the stone structure.  Deposition of silt and sediment has occurred downstream in areas where velocity was reduced, as expected and desired, creating substrate diversity within and behind the structures themselves.  Minor scour and undercutting was noted around the upstream and lateral bases of the boulders at the Boulder Field.  In general, fouling of the locations was minor, and was primarily from debris (sticks and aluminum beverage cans). 

Prior to construction of the structures, few, if any fish were observed at these locations, and their use after the first year indicates that habitat at these locations is much improved.  At all four locations, smallmouth bass in multiple age classes and at substantial densities, appeared to be using the structures and the water column just above them.  Divers observed fish using the cover provided by the rocks and logs, as well as the velocity breaks that the structures created.

These results from the year one monitoring event indicate that the fish attraction structures are performing well. The next scheduled monitoring event will be conducted in year four (2012) to provide additional information on the physical condition and utilization of the fish attraction structures in the Niagara River.

 

7.0     REFERENCES

Kleinschmidt Associates and Riveredge Associates.  2005.  Investigation of Habitat Improvement Projects for the Niagara Power Project, Niagara Power Project, FERC No. 2216 – Volume 1: Public.  Prepared for New York Power Authority, White Plains, NY. August.

Kleinschmidt Associates.  2009.  Fish Attraction Structure Monitoring Plan. Niagara Power Project, FERC No. 2216.  Prepared for New York Power Authority, White Plains, NY. June.

 

APPENDIX A
2009 FIELD DATA COLLECTION FORMS

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