ML073340908
ML073340908 | |
Person / Time | |
---|---|
Site: | Indian Point ![]() |
Issue date: | 01/31/2007 |
From: | ASA Analysis & Communication |
To: | Dynegy Roseton, Entergy Nuclear Indian Point 2, Entergy Nuclear Indian Point 3, Mirant Bowline, Office of Nuclear Reactor Regulation |
References | |
Download: ML073340908 (38) | |
Text
CHAPTER 2 MATERIALS AND METHODS 2.1 SAMPLING DESIGN Several fishery techniques were employed in three separate sampling surveys to obtain comprehensive information on the abundance and distribution of selected larval, juvenile or young-of-year (YOY), and adult fish species in the Hudson River estuary. Temporally, the monitoring program encompassed the spring through fall season, the period of greatest biological activity in northern U.S. temperate waters. The surveys were designed to sample the full range of Hudson River habitat toward a representative assessment of species-specific spatial distribution patterns. During 2005, survey-specific techniques were employed which were consistent with previous Hudson River Monitoring Programs.
The scope and objectives of the three sampling surveys comprising the overall monitoring program are summarized as follows.
- 1. Longitudinal River Ichthyoplankton Survey (LRS or Long River Survey)
Sampling encompassed the entire length of the Hudson River estuary, from River Mile (RM) 1 at the Battery in Manhattan to RM 152 at the Federal Dam in Troy.
The LRS yielded ichthyoplankton data to support calculations of standing crop, temporal and geographic indices, and growth rates for selected Hudson River fish species. The primary species were Atlantic tomcod (Microgadus tomcod),
American shad (Alosa sapidissima), striped bass (Morone saxatilis), white perch (M. americana) and bay anchovy (Anchoa mitchilli). LRS sampling was concentrated during the spring, summer, and early fall when eggs and larvae of the primary species have historically been abundant.
- 2. Fall Juvenile Survey (FJS or Fall Shoals Survey)Samples were collected every other week from the Battery to the Troy Dam in mid-summer and fall. The objective was to provide data on YOY fish to support calculation of standing crop and temporal and geographic indices for selected Hudson River fish species.
The target species were Atlantic tomcod, American shad, striped bass, and white perch.
- 3. Beach Seine Survey (BSS)Beach seine samples were collected in alternate weeks relative to the FJS at stations ranging from the George Washington Bridge (RM 12) to the Troy Dam. The objective was to obtain distribution and relative abundance information on YOY American shad, Atlantic tomcod, striped bass, and white perch during periods when these species were concentrated primarily in the shallow, near-shore areas. The survey was conducted from mid-June through October, when YOY of these species were typically abundant in the shorezone nursery areas.
Sampling for all surveys was conducted according to a stratified random design in which the Hudson River estuary from the Battery (RM 1) to the Federal Dam at Troy (RM 152) was divided into 13 regions (Figure 2-1). Each region was further divided into "strata" on the basis of river depth. The strata, based on river depth, are graphically presented in Figure 2-2 and defined below:
2005 Year Class Report 2-1
- ShoreThat portion of the Hudson River estuary extending from the shore to a depth of 10 ft (the stratum defined only for BSS).
- Shoal That portion of the Hudson River estuary extending from the shore to a depth of 20 ft at mean low tide.
- BottomThat portion of the Hudson River estuary extending from the bottom to 10 ft above the bottom where river depth is greater than 20 ft at mean low tide.
- ChannelThat portion of the Hudson River estuary not considered bottom where river depth is greater than 20 ft at mean low tide.
The relative area and configuration of the shoal, bottom, and channel strata vary over the length of the Hudson River estuary but may be characterized using the three cross section views presented in Figure 2-2. For example, the low relief sectional is characteristic of the Tappan Zee and Croton-Haverstraw regions, the high relief sectional is exemplified by the Yonkers and Poughkeepsie regions, and the fjord relief sectional represents the West Point region.
A minimum of two samples was assigned to each stratum in most regions for the LRS.
However, no samples were allocated in the Poughkeepsie through Albany regions during the first three sampling weeks of the LRS (14 March - 1 April) nor in the Hyde Park through Albany regions during the final seven sampling weeks of the LRS (11 July - 7 October) because few organisms of the target species were historically present in these regions during these weeks.
A minimum of two samples was assigned to each stratum in each region for the FJS except no channel samples were allocated during the final three sampling weeks (24 October - 2 December). A minimum of three samples was allocated in each region for the BSS. Shoal strata samples were not assigned in upriver regions nor were shoal or shore strata samples assigned in the Battery region. The strata actually sampled in each region during the 2005 survey period are presented in Table 2-1.
A general summary of the three sampling surveys for the annual monitoring program is presented in Table 2-2. The field and laboratory methods used for each survey are described in detail in the following sections.
2.2 LONGITUDINAL RIVER ICHTHYOPLANKTON SURVEY 2.2.1 Field Methods The 2005 LRS was performed over a period of 30 weeks from 14 March to 7 October (Table 2-2 and Figure 2-3). For the first three weeks, sampling was conducted between RM 1 and RM 61 with all samples collected during the day. For the next seven weeks beginning 4 April, weekly sampling encompassed RM 1 to RM 152 with samples continuing to be collected during the day. Beginning the week of 23 May for six consecutive weeks sampling was conducted at night between RM 1 and RM 152. In the final phase of sampling from 11 July through 7 October, sampling was conducted biweekly between RM 1 and RM 76 with all samples collected at night.
Between 16 May and 9 September, approximately 10 additional trawl (channel strata) samples were collected per sampling week. These samples were specially preserved so that aging of striped bass larvae could be conducted. In 2005, sampling was conducted for two additional weeks, one in November and one in December. These samples were collected systematically (every 5 river miles) from RM 0 to RM 60 during the day.
2005 Year Class Report 2-2
The allocation of sampling effort among river regions and strata was temporally adjusted in response to the projected presence and distribution of target species and life stages. The 2005 LRS sampling program was scheduled as 6 separate multi-week efforts. The first sampling effort, performed in March, focused on the collection of Atlantic tomcod post yolk-sac larvae (PYSL). The second effort, performed during April, focused on the collection of American shad eggs. The third effort, from late April to mid-May, was designed to collect eggs of Morone spp.
and American shad. The fourth effort, performed from mid-May through early June, targeted Morone spp. and American shad yolk-sac larvae (YSL). The fifth effort, in June and early July, was designed to collect Morone spp. and American shad PYSL. The LRS sampling program concluded with a 13-week period, sampled biweekly, from the middle of July to early October.
The final sampling effort was designed to collect all life stages of bay anchovy. The additional samples collected in November and December targeted the early life stages of Atlantic croaker.
The allocation of sampling effort among regions and strata is presented in Table 2-3. Of the 3,647 ichthyoplankton samples (including 125 striped bass otolith aging samples) scheduled for collection during 2005, 3,619 samples were collected, accounting for 99 percent of the scheduled total. All of the 84 scheduled samples in the Atlantic Croaker Ichthyoplankton Survey were collected.
Two distinct gear types were used for field collections during the 2005 LRS:
- 1.0-m2 Tucker trawl (Figure 2-4 and Table 2-4) to sample the shoal and channel strata (non-bottom), and
- 1.0-m2 epibenthic sled (Figure 2-5 and Table 2-4) to sample the bottom-only shoal and channel strata.
Both gear types were towed against the prevailing current for 5 minutes. The tow started with the remote opening of the net and terminated with its remote closing. If the river depth was 20 ft or less, an open set and retrieval of the net was performed. The tow speed for the Tucker trawl was adjusted to maintain a towing wire angle of approximately 45o averaging approximately 0.9 m/second. The tow speed for the epibenthic sled-mounted net was maintained at approximately 1.0 m/second. An electronic flowmeter mounted along the side of the research vessel and equipped with an on-deck readout display was used to establish and maintain tow speed. A calibrated digital flowmeter mounted in the center of the net mouth was used to calculate the volume of water filtered for each sample.
Following deployment and retrieval of the sampling gear, net washing was performed to concentrate the sample into the codend bucket. The samples were then examined for yearling and older fish which were identified, enumerated, and returned to the Hudson River estuary.
Special care was taken to observe sturgeon species for physical condition and for the presence of marks and/or tags. All yearling and older sturgeon were measured to the nearest millimeter, weighed to the nearest gram, and, if alive, returned to the river or, if dead, frozen and saved for the NYSDEC. After yearling and older fish were removed, the remaining sample was placed in container(s) so that the sample occupied no more than 25 percent of the container volume. The containers were filled with a 10 percent aqueous formalin solution.
In situ measurements of water temperature (°C), dissolved oxygen (mg/L), and specific conductance (microsieman/cm at 25°C) were taken with calibrated meters at fixed river mile and strata stations in conjunction with the biological sampling. The number of physical/chemical sampling locations, by river mile and strata, are presented in Table 2-5 for the 2005 LRS.
Physical/chemical measurements were recorded from surface, mid-depth, and bottom water depth at channel stations and from the surface and bottom water depth at shoal stations.
2005 Year Class Report 2-3
During the 23 collection weeks of the 2005 LRS, 3,520 physical/chemical measurements were scheduled and all measurements actually recorded, accounting for 100 percent of the scheduled total. During the additional sampling weeks in November and December, an additional 214 physical/chemical measurements were recorded.
Ichthyoplankton samples collected for striped bass otolith aging were handled in the same manner as regularly scheduled LRS samples except that a 95 percent ethanol preservative was substituted. Within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />, the samples were drained and placed in fresh 95 percent ethanol.
2.2.2 Laboratory Methods In 2005, approximately 70 percent of the regular LRS samples were selected for laboratory analysis. Selection of samples for laboratory analysis began with the grouping of samples according to river run (i.e., sampling week), region, and strata. Based on these groupings, samples were selected based on one of the following criteria:
- 1. If there were less than 6 samples in the group, then all were selected for analysis.
- 2. If there were between 6 and 12 samples in the group, then 50 percent of the samples were randomly selected for analysis.
- 3. If there were more than 12 samples in the group, then 20 percent of the samples were randomly selected for analysis.
The allocation of samples for laboratory analysis among regions, strata, and gear types based on these criteria is listed in Table 2-6. The total number of analyzed samples for 2005 was 2,433, comprising 69.6 percent of the collected samples (excluding those collected for otolith analysis). All of the 84 samples collected during the Atlantic Croaker Ichthyoplankton Survey were analyzed.
In 2005, as in previous years, splitting (or subsampling) was permitted. A trained technician first determined, by visual inspection, if the sample needed splitting. Samples containing large numbers of eggs may have been split so that eggs were only sorted from one or more aliquots containing a total of at least 250 eggs (all species combined).
Two different sets of criteria were used for subsampling of larval stages, depending on the river run. Beginning with the river run in which striped bass PYSL first appeared, and for the next 8 river runs (a total of 9 consecutive river runs), a minimum of 500 Morone larvae (i.e., the combined total of YSL, PYSL, and YOY of striped bass, white perch, and unidentified Morone) was sorted from the entire sample and a minimum of 50 non-Morone larvae was also sorted.
Because some of the more difficult distinctions between species (e.g., striped bass versus white perch) or between life stages could not be made reliably during sorting, samples from these 9 river runs were typically sorted in their entirety for larvae (i.e., YSL, PYSL, and YOY combined) of all species combined. An exception to this may have been made, at the discretion of the laboratory supervisor, under the following circumstances: when extremely large numbers of non-Morone larvae occurred in the sample and a qualified identifier had verified that sufficient numbers of both Morone larvae and non-Morone larvae were sorted to meet their respective subsampling quotas. The purpose of this exception was to allow splitting before sorting of taxa such as clupeids which could readily be distinguished from Morone by sorters.
2005 Year Class Report 2-4
The second set of criteria for subsampling larvae applied to the 13 other river runs not covered in the previous paragraph (before and after the period of striped bass abundance). Any sample from these river runs may have been subsampled so that larvae were sorted from one or more splits containing at least 100 larvae (i.e., YSL, PYSL, and YOY combined) of all species combined.
To eliminate bias, some steps in the splitting procedure were performed by an assistant so that the sorter had no prior knowledge of which splits were to be used for the analysis. This procedure is explained in Figure 2-6. Randomness of the splitting procedure was monitored and demonstrated by testing selected samples to determine whether splits from the same sample differed by more than random variation. Samples were selected to test for randomness by a continuous sampling plan, shown in Figure 2-7 (CSP-V from MIL-STD-1235, AOQL = 10 percent).
For each split sample evaluated, three fractions of the same aliquot size were sorted and compared by the chi-square test according to the following procedure. The counts of the three splits (including any quality control [QC] finds) were averaged to obtain the expected value for the sample. Chi-square was calculated as:
chi square = (O1 E ) 2 + (O2 E ) 2 + (O3 E ) 2 E E E where O1, O2, and O3 = Observed counts for splits 1, 2, and 3.
E = Expected value for the sample (average of O1, O2, and O3).
If the calculated value for chi-square was less than 5.99, then the splits of that sample were considered random, and the sample passed the split QC (5.99 was the critical value of chi-square with two degrees of freedom at an alpha level of 0.05). If a sample was split for both eggs and larvae, then both stages were tested separately. The sample passed the split QC only if chi-square was below the critical value for both life stages.
Eggs and larvae were separated from detrital material, sorted by major taxonomic group and life stage, counted, and placed in vials containing 5 percent formalin or in ethyl alcohol. Sorted samples were evaluated by a trained technician under magnification and all organisms were identified and enumerated. The following life stage designations were used in identification:
Life Stage Description Egg Embryonic stage from spawning to hatching, YSL From hatching to development of a complete and functional digestive system, PYSL From development of a complete digestive system to transformation to juvenile form, and YOY From completed transformation to Age 1.
Whenever possible, a maximum of 30 striped bass, 30 white perch, 30 American shad, 30 Atlantic tomcod, and 30 bay anchovy per sample were measured. Organisms were chosen at random from each taxon regardless of life stage until the required numbers were obtained; life 2005 Year Class Report 2-5
stages to be included were YSL, PYSL, and YOY. The total length of YSL and PYSL was measured to the nearest 0.1 mm and to the nearest 1 mm for YOY. Measurements were recorded on the laboratory data sheet. Selection of specimens for measuring was randomized by spreading them uniformly in a gridded container, selecting a starting point in the grid by means of a random number table, and then measuring the first 30 measurable specimens encountered in a predetermined pattern commencing at the starting point. Every grid space had an equal probability of being selected as the starting point, so every specimen had an equal probability of being included in the subsample.
Continuous sampling inspection was employed during the sort and identification procedures to ensure an average outgoing quality limit of 10 percent or better. Two sampling modes were required in the continuous sampling plan (CSP-1):
Mode 1The first eight samples sorted or analyzed for larval identification by an individual are subject to 100 percent QC reanalysis. If all eight pass the reanalysis, i.e., if <10 percent of the ichthyoplankton are missed or misidentified per sample, the individual is placed in CSP Mode 2. If any sample fails during Mode 1, then Mode 1 is continued until eight consecutive samples pass. For example, if a sample with QC No. 7 fails, then samples with QC Nos. 8 through 15 are subject to QC resorting.
Mode 2Lots of seven consecutive samples per individual are assigned for identification QC and per laboratory facility for sort QC. One sample from each lot is randomly chosen for QC analysis. If a sample fails (>10 percent of organisms missed or misidentified) during Mode 2, the individual is placed back into Mode 1.
For example, if a sample with QC No. 6 fails in a lot of seven samples, then samples with QC Nos. 7 through 14 are subject to QC reanalysis. If samples 7 through 14 pass, the individual is again placed in Mode 2.
Results of the 2005 CSP-1 Quality Control Program are contained in Appendix A.
2.3 FALL JUVENILE SURVEY 2.3.1 Field Methods The 2005 FJS biweekly sampling program extended from RM 1 to 152 and covered 22 weeks from 4 July to 2 December (Figure 2-3). Samples were collected at night for the first 8 river runs from 4 July through 14 October, and during the day for last 3 river runs from 24 October through 2 December. These last river runs, which were conducted with a modified sampling design, were intended to examine Atlantic tomcod distribution. Table 2-7 presents the distribution of the FJS sampling effort among the 13 river regions by stratum. Of the 2,130 samples scheduled for collection, 2,128 were actually collected, yielding 99.9 percent completion.
A 1.0-m2 Tucker trawl and a 3.0-m beam trawl were used to collect YOY fish in the 2005 FJS.
The Tucker trawl with 3.0-mm mesh was used to collect samples in the channel stratum, while the beam trawl (Figure 2-8) was used to sample the shoal and bottom strata. The latter gear was first used in this capacity in the 1985 FJS; prior to 1985, an epibenthic sled-mounted Tucker trawl was used. With the modified sampling design of the last 3 river runs from 24 October through 2 December, no channel samples or Tucker trawl samples were scheduled for collection. Only beam trawl samples in the shoal and bottom strata were taken during these river runs. Design specifications for FJS gear currently in use are listed in Table 2-8.
2005 Year Class Report 2-6
Both gear types were towed against the prevailing current for approximately 5 minutes. For the Tucker trawl, vessel speed was adjusted as necessary to achieve and maintain a 45° wire angle; the resultant tow speed was recorded. The beam trawl was towed at a speed of approximately 1.5 m/second. Tow speed was established and maintained by use of an electronic flowmeter mounted along the side of the research vessel and equipped with an on-deck readout display. Tucker trawl samples taken in greater than 20 ft of river depth were remotely opened and closed at sampling depth. A calibrated digital flowmeter mounted in the center of the net mouth was used to calculate the volume of water filtered for each sample.
Calibrated water quality instruments were used to measure water temperature (°C), dissolved oxygen (mg/L), and specific conductance (microsieman/cm at 25°C) at fixed river mile and strata stations in conjunction with field sampling. Sampling locations were the same as those used for the 2005 LRS sampling program (Table 2-5). Measurements of physical/chemical parameters were recorded from surface, mid-, and bottom water depths at channel stations and from surface and bottom water depths at shoal stations. During the 2005 FJS, of the 2,002 samples scheduled for collection, 2,002 were actually collected, yielding 100 percent completion.
Because of the difficulty in differentiating some species, especially YOY Morone (striped bass, white perch) and Alosa (alewife, blueback herring), samples collected during the first three sampling periods (River Runs 1 through 3) for the 2005 FJS program were preserved with 10 percent formalin at the time of collection and returned to the laboratory for analysis. Before preservation, samples were examined for fish determined to be yearling or older, based on length categorization; live fish were returned to the river after count data were determined.
Beginning with the fourth biweekly sampling period, samples were evaluated in the field; only fish required to fill length measurement and food habit quotas were returned to the laboratory.
The quota was to be 20 specimens of a selected species from each river region per river run; because of the necessity of returning fish to the river alive, the first 20 specimens of a selected species were brought to the laboratory for length measurements. The Hyde Park through Albany regions were considered one region for the purpose of filling length measurement quotas during the entire FJS and during River Runs 4 through 10 of the BSS. Also for the BSS during River Runs 1 through 3, the Yonkers through West Point regions were considered as one region for the same purpose. In river regions where fewer than 10 samples were collected per survey, no more than 10 specimens of each selected species from an individual sample were used to fill the length measurement quota. This criterion was used in the following surveys for the specified river regions:
Sampling Program Region BSS YK, IP, WP, CW, PK FJS WP, PK In all other regions, when the sample schedule resulted in 10 or more samples per survey, no more than 5 specimens per species in a sample were used to fill the length measurement quotas. If more specimens of a species were collected than needed, the individuals used to fill the quotas were randomly selected.
All fish not returned to the laboratory were identified and enumerated into length classes as described in the following section. All Atlantic sturgeon, shortnose sturgeon, and striped bass 2005 Year Class Report 2-7
were examined for external and internal magnetic tags. All sturgeon were measured to the nearest millimeter, weighed to the nearest gram, and, if alive, returned to the river or, if dead, frozen and saved for the NYSDEC. All striped bass with external streamer tags were measured and a scale sample was taken.
2.3.2 Laboratory Methods Fish from the FJS in both the field and laboratory were identified and enumerated into the following length classes:
Length Class 1Less than or equal to the YOY length limit ("Division 1"), which was determined by the field contractor on a weekly basis for each species.
Length Class 2Greater than Division 1 and less than or equal to the yearling length limit ("Division 2"); set at 150 mm for most species, also determined weekly by the field contractor. From 1 January through 31 May, Division 2 represents the upper length limit for yearling fish for all species. From 1 June through 31 December, Division 2 is assigned a static value of 150 mm total length for all species except alewife, American shad, blueback herring, striped bass, Atlantic tomcod, and white perch. For these species, Division 2 is maintained as a dynamic upper length limit for yearling fish throughout the year.
Length Class 3Greater than Division 2 and less than or equal to 250 mm.
Length Class 4Greater than 250 mm.
Twenty specimens of the following selected species collected in each river region per river run were measured for total length (nearest millimeter) in the laboratory (except for sturgeon species which were measured in the field):
- Shortnose sturgeon
- American shad
- Spottail shiner
- Atlantic sturgeon
- Striped bass
- Atlantic tomcod
- Weakfish
- Bay anchovy
- White catfish
- Blueback herring
- White perch.
2.4 BEACH SEINE SURVEY 2.4.1 Field Methods The 2005 BSS utilized a 30.5-m (nominal 100ft) total length beach seine to collect YOY fish in the shorezone of each region, except the Battery region. Table 2-9 presents specifications for the beach seine. One end of the net was held on shore and the other end was towed perpendicularly away from the shore by boat. The seine was then hauled, clockwise if possible, in a semicircular path toward shore. The complete beach seine deployment swept an area of approximately 450 m2 (TI 1981). All BSS samples were collected on a diurnal schedule during alternate weeks of the FJS.
The 2005 BSS biweekly sampling program was conducted from 13 June through 21 October (Figure 2-3). Ten of the 19 weeks in this time period were collection weeks with 100 beach 2005 Year Class Report 2-8
seine samples per week scheduled for collection. Allocation of the total number of samples by river region collected for the 2005 BSS is presented in Table 2-10. Of the 1,000 samples projected for collection in 2005, 1,000 were collected, yielding 100 percent completion.
Measurements of water temperature (°C), dissolved oxygen (mg/L), and specific conductance (microsieman/cm at 25°C) were taken with each beach seine sample using in-situ water quality instrumentation. Physical/chemical measurements were taken 1 ft below the water surface and approximately 50 ft from the shoreline. During the 10 collection weeks of the 2005 BSS, all of the 1,000 scheduled water quality samples were collected.
YOY fishes collected during the first four beach seine river runs in 2005 were processed in the laboratory because of the difficulty in distinguishing species at the YOY life stage; adults were processed in the field. Beginning with River Run 5, all samples were field processed; 20 specimens of the selected species from each region per run were collected (as described in Section 2.3.1) for length determination in the laboratory. Samples maintained for laboratory analysis were preserved using 10 percent formalin. Fish from the BSS in both the field and laboratory were identified and enumerated into length classes as described in Section 2.3.2.
Any sturgeon collected during the BSS were measured to the nearest 1 mm and weighed to the nearest 1 g. Fish that remained alive were returned to the Hudson River estuary; dead fish were frozen and held for NYSDEC. All sturgeon and striped bass were examined for external and internal magnetic tags. Striped bass with external tags were measured and a scale sample was taken.
2.4.2 Laboratory Methods All fish returned to the laboratory were measured for total length to the nearest 1.0 mm.
Laboratory analysis was conducted in the same manner as described for samples collected during the FJS.
2.5 ANALYTICAL METHODS 2.5.1 Physical/Chemical Parameters To display the spatial and temporal patterns of temperature, salinity, and dissolved oxygen, a mean of each parameter for each sampling location and sampling week, weighted by stratum volume, was calculated. Equation 1 was used to compute these means for the standard physical/chemical stations sampled in conjunction with the LRS and FJS. Equation 2 was used for data collected in conjunction with the BSS. Salinity data were computed from conductivity data (microsieman/cm at 25°C) using Equation 3 (TI 1976). This equation differs from that used in some of the previous Year Class reports in that pressure data are not required. The maximum deviation between this equation and the previous equation is 0.1 percent (TI 1976).
nlw nklw ndklw Wlw = Pkr [ 1/n d=1 klw ( 1/n dklw Widklw )] (1) k=1 i=1 where Wlw = Weighted mean of a physical/chemical parameter at sampling location l during week w of the LRS and FJS.
2005 Year Class Report 2-9
Widklw = Physical/chemical measurement for location i at depth d in stratum k at sampling location l during week w.
Pkr = Proportion of the river volume of region r containing sampling location l that is contained by stratum k (bottom and channel strata were combined for water quality analysis).
ndklw = Number of sites at which measurements were made at depth d in stratum k at sampling location l during week w.
nklw = Number of depths sampled in stratum k at sampling location l during week w.
nlw = Number of strata sampled at sampling location l during week w.
nrw Wrw = 1/ nrw Wirw (2) i=1 where Wrw = Mean of a physical/chemical parameter at river mile r during biweek w of the BSS.
Wirw = Physical/chemical measurement for location i at river mile r during biweek w.
nrw = Number of physical/chemical measurements taken at river mile r during biweek w.
Salinity = -100 ln ( 1 - C25/178.5) (3) where C25 = Conductivity (millisieman/cm at 25°C).
2005 Year Class Report 2-10
2.5.2 Spatiotemporal Distribution Indices 2.5.2.1 Density and Catch-Per-Unit-Effort Estimates Estimates of population densities were made for the LRS and FJS. Data collected during the Atlantic Croaker Ichthyoplankton Survey in November and December were excluded from population density estimates for the LRS because the sampling design differed (systematic versus stratified, random design). For these two surveys the number of fish (by species and life stage) captured in individual samples was first converted to density (no./m3 of water sampled) using Equation 4. The mean density and the standard error of the mean were calculated for each stratum, region, and sampling week using Equations 5 and 6. To obtain a mean density and standard error for each region during each sampling week, the stratum densities were weighted by the proportion of the regional river volume found in the stratum (Equations 7 and 8).
If a stratum was not sampled, its volume was added to the volume of an adjacent stratum that was sampled. Stratum volume adjustments were made according to the following rules:
If This Stratum Its Volume Was Added Was Not Sampled To This Stratum Shoal Bottom Bottom Channel Channel Bottom Cikrw Dikrw = (4)
Vikrw where Dikrw = Density (for a life stage and species)/m3 for sample i in stratum k in region r during week w.
Cikrw = Number of fish caught in sample i in stratum k in region r during week w.
Vikrw = Volume sampled (m3) by sample i in stratum k in region r during week w.
n krw 1
Dkrw =
n krw D
i=1 ikrw (5) where Dkrw = Average density in stratum k in region r during week w.
Dikrw = Sample density calculated in Equation 4.
nkrw = Number of samples taken in stratum k in region r during week w.
2005 Year Class Report 2-11
nkrw (D Dkrw )
2 ikrw SE(Dkrw) = i =1 (6)
(nkrw )(nkrw 1) where SE(Dkrw) = Standard error of the average density in stratum k in region r during week w.
Dikrw = Sample density calculated in Equation 4.
Dkrw = Average stratum density calculated in Equation 5.
nrw Drw = (Dkrw)(Pk) (7) k=1 where Drw = Average density in region r during week w.
Dkrw = Average stratum density calculated in Equation 5.
Pk * = Proportion of the regional river volume found in stratum k (Table 2-11).
nrw = Number of strata sampled in region r during week w.
[SE(D ]
n rw SE(Drw) = krw ) 2 (Pk ) 2 (8) k =1 where SE(Drw) = Standard error of average density in region r during week w.
SE(Dkrw) = Standard error of the average stratum density calculated in Equation 6.
Catches from the BSS were reported as number caught per seine haul (catch-per-unit-effort
[CPUE]) by life stage and species. The average CPUE for a region and its standard error were calculated using Equations 9 and 10:
When a stratum is missing, Pk for the sampled stratum is equal to the sum of the Pk for the sampled stratum and the Pk for the unsampled stratum.
2005 Year Class Report 2-12
n rw 1
Crw =
n rw C
i= 1 irw (9) where Crw = Average CPUE in region r during week w.
Cirw = CPUE for sample i in region r during week w.
nrw = Number of samples taken in region r during week w.
nrw SE(Crw) = (Cirw - Crw)2 (10) i=1 nrw(nrw - 1) where SE(Crw) = Standard error of average CPUE in region r during week w.
Crw = Average regional CPUE calculated in Equation 9.
2.5.2.2 Standing Crop Estimates An index of standing crop (the number of fish in an area at a particular time) was estimated by life stage and species for each of the three surveys. Again, data collected during the Atlantic Croaker Ichthyoplankton Survey in November and December were excluded from standing crop indices for the LRS because the sampling design differed (systematic versus stratified, random design). Standing crop indices and the associated standard errors were calculated for each stratum in a region by taking the product of the average stratum density (or the standard error) and the volume of water contained in that stratum (Equations 11 and 12 for the LRS and FJS)
(Table 2-11). The regional standing crop index was then estimated as the sum of the stratum index values (Equations 13 and 14). Similarly, an estimate of the standing crop index for the Hudson River estuary for each week was calculated by summing the standing crops for the 13 (12 for the BSS) river regions (Equations 15 and 16). This value is an index rather than an absolute standing crop value because no adjustment was applied for collection efficiency.
SCkrw = (Vkr)(Dkrw) (11) where SCkrw = Standing crop index for stratum k in region r during week w.
Vkr = River volume contained by stratum k in region r.
2005 Year Class Report 2-13
Dkrw = Average stratum density calculated in Equation 5.
SE(SCkrw) = (Vkr)[SE(Dkrw)] (12) where SE(SCkrw) = Standard error of the standing crop index for stratum k in region r during week w.
SE(Dkrw) = Standard error of average stratum density calculated in Equation 6.
3 SCrw** = SCkrw (13) k=1 where SCrw = Standing crop index for region r during week w.
SCkrw = Stratum standing crop index calculated in Equation 11.
3
[SE(SC )]
2 SE(SC)rw ** = krw (14) k =1 where SE(SCrw) = Standard error of standing crop index for region r during week w.
SE(SCkrw) = Standard error of stratum standing crop index calculated in Equation 12.
12 SCw = SCrw (15) r=1 where SCw = Standing crop index for week w. For the LRS and FJS, regional standing crop indices include the Battery Region (r=0).
Volumes of unsampled strata were added to the volumes of an adjacent stratum according to the rules for stratum volumes in Section 2.5.2.
2005 Year Class Report 2-14
SCrw = Regional standing crop index calculated in Equations 13 or 17.
12 SE(SCw) = [SE(SC )]
r =1 rw 2
(16) where SE(SCw) = Standard error of standing crop index for week w. For the LRS and FJS, regional standing crop indices include the Battery Region (r=0).
SE(SCrw) = Standard error of regional standing crop index calculated in Equations 14 or 18.
An index of regional standing crop (and standard error) for the BSS was obtained by multiplying CPUE and the surface area of the shorezone and dividing by the empirically derived estimate of the area sampled by the 30.5-m beach seine (Equations 17 and 18). The weekly index of standing crop for the shorezone was calculated as the sum of the 12 regional standing crops (Equations 15 and 16).
SCrw = (Crw Ar) / A (17) where SCrw = Standing crop index for the shorezone in region r during week w.
Crw = Average regional CPUE calculated in Equation 9.
Ar = Surface area (m2) of the shorezone in region r.
A = Surface area (m2) sampled by the beach seine (450 m2) (TI 1981).
SE(SCrw) = [SE(Crw)] (Ar) (18)
A where SE(SCrw) = Standard error of standing crop index for the shorezone in region r during week w.
SE(Crw) = Standard error of average regional CPUE calculated in Equation 10.
2.5.2.3 Temporal and Geographic Distribution Indices 2005 Year Class Report 2-15
Distribution indices were computed to facilitate presentation of changes in distribution of selected species and life stages through time and space. To allow comparisons of 2005 data with historical data, only data from samples collected from Weeks 18 to 26 (where Week 1 begins with the first Monday in January) were used for LRS (except for bay anchovy which used Weeks 18-40); data from Weeks 33 to 40 were used for the FJS and BSS. In all cases, data were used only when Regions 1-12 were sampled (except for bay anchovy which included Region 0).
The LRS was used for calculating the temporal and geographic indices for early life stages of striped bass, white perch, Atlantic tomcod, bay anchovy, American shad, Alosa spp., and rainbow smelt. The FJS was used to calculate geographical distribution indices for hogchoker, white catfish, and weakfish. The BSS was used to calculate geographical distribution indices for striped bass, white perch, bay anchovy, American shad, alewife, blueback herring, gizzard shad, spottail shiner, and bluefish.
The periods used for the LRS and BSS spanned 1974-2005, whereas the time period for the FJS extended from 1979 (when the FJS sampled the river from RM 12 to RM 152) through 2005. Temporal and geographic indices for bay anchovy from the LRS used the period from 1988 to 2005, when the sampling design included the Battery region.
A geographic index that collapses data over weeks was calculated for LRS, FJS, and BSS data as the relative standing crop in each region. This geographic index was calculated as follows:
ny SCrwy Gry = w=1 (19) 12 ny SCrwy r=1 w=1 where Gry = Geographic index for region r in year y.
SCrwy = Regional standing crop index for region r in week w in year y calculated in Equations 13 or 17.
ny = Number of weeks sampled in year y.
A temporal index that collapses data for the entire Hudson River estuary was computed for early life stages from LRS standing crop indices (Equation 20):
SC wy Twy = ny (20)
SC w =1 wy where 2005 Year Class Report 2-16
Twy = Temporal index for week w in year y.
SCwy = Weekly standing crop index in year y calculated in Equation 15.
ny = Number of weeks sampled in year y.
Link to Chapter 3 2005 Year Class Report 2-17
REGION RIVER MILES NEW YORK STUDY AREA ALBANY (125-152)
CATSKILL (107-124)
MASSACHUSETTS SAUGERTIES (94-106)
KINGSTON (86-93)
HYDE PARK (77-85)
POUGHKEEPSIE (62-76) DANSKAMMER ROSETON CORNWALL (56-61)
WEST POINT (47-55)
INDIAN POINT (39-46) LOVETT INDIAN POINT BOWLINE CROTON-HAVERSTRAW (34-38)
CONNECTICUT NEW YORK TAPPAN ZEE (24-33)
NEW JERSEY YONKERS (12-23)
BATTERY (0-11)
Atlantic Ocean Figure 2-1. Location of 13 geographic regions (with river mile boundaries) sampled during the 2005 biological monitoring program in the Hudson River estuary.
Night Day Key:
Sampling Sampling Long River Survey Striped bass Atlantic Croaker Otolith Survey Ichthyoplankton Survey MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Fall Juvenile Survey MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Beach Seine Survey MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Figure 2-3. Completed sampling schedule for 2005.
Table 2-1 Strata Sampled within the 13 Geographic Regions of the Hudson River Estuary During 2005 River 2005 Surveys Region Abbreviation River Miles Kilometers Shore Shoal Channel Bottom Battery BT 1-11 1-19 -- -- X X Yonkers YK 12-23 19-39 X X X X Tappan Zee TZ 24-33 39-55 X X X X Croton-Haverstraw CH 34-38 55-63 X X X X Indian Point IP 39-46 63-76 X X X X West Point WP 47-55 76-90 X -- X X Cornwall CW 56-61 90-100 X X X X Poughkeepsie PK 62-76 100-124 X -- X X Hyde Park HP 77-85 124-138 X -- X X Kingston KG 86-93 138-151 X -- X X Saugerties SG 94-106 151-172 X -- X X Catskill CS 107-124 172-201 X -- X X Albany AL 125-152 201-246 X -- X X NOTE: Dashes (--) indicate no sampling scheduled.
2005 Year Class Report
Table 2-2 Summary of 2005 Hudson River Surveys Sampling Schedule Sample Number Start End Number of Sampling Strata Collection Lab Program Phase Week Week River Runs Frequency Sampled Projected Actual Analysis Sampling Gear Longitudinal River 1 MAR 8 OCT 23 Weekly/ Shoal 588 586 554 1.0-m2 net on epibenthic Ichthyoplankton Biweekly sled, or 1.0-m2 Tucker Survey trawl Channel 1,6701 1,670 957 1.0-m2 Tucker trawl Bottom 1,389 1,363 922 1.0-m2 net on epibenthic sled Atlantic Croaker 14 NOV 5 DEC 2 Monthly Shoal 32 32 32 1.0-m2 net on epibenthic Ichthyoplankton sled, or 1.0-m2 Tucker Survey trawl Channel 26 26 26 1.0-m2 Tucker trawl Bottom 26 26 26 1.0-m2 net on epibenthic sled Fall Juvenile 4 JUL 28 NOV 11 Biweekly Shoal 427 426 3.0-m beam trawl, or Survey 1.0-m2 Tucker trawl Channel 648 648 1.0-m2 Tucker trawl Bottom 1,055 1,054 3.0-m beam trawl Beach Seine 13 JUN 17 OCT 10 Biweekly Shore 1,000 1,000 30.5-m beach seine Survey 1
Includes 125 samples for striped bass otolith analysis.
2005 Year Class Report
Table 2-3 Summary of 2005 Sample Collection Information by River Region and Stratum for the Longitudinal River Ichthyoplankton Survey 3-Week Period from 14 MAR to 1 APR 3-Week Period from 4 APR to 22 APR 3-Week Period from 25 APR to 13 MAY Shoal Bottom Channel Shoal Bottom Channel Shoal Bottom Channel Region Sled Trawl Sled Trawl Total Sled Trawl Sled Trawl Total Sled Trawl Sled Trawl Total Battery -- -- 15 15 30 -- -- 24 18 42 -- -- 18 18 36 Yonkers 6 6 17 18 47 6 6 21 15 48 6 6 21 15 48 Tappan Zee 9 6 18 18 51 18 12 12 12 54 18 12 12 12 54 Croton-Haverstraw 9 6 18 18 51 12 9 12 12 45 12 9 12 12 45 Indian Point 6 6 18 18 48 6 6 12 12 36 6 6 18 30 60 West Point -- -- 15 15 30 -- -- 15 15 30 -- -- 18 45 63 Cornwall 6 4 12 12 34 9 6 9 9 33 9 6 24 15 54 Poughkeepsie -- -- -- -- -- -- -- 9 9 18 -- -- 30 30 60 Hyde Park -- -- -- -- -- -- -- 9 21 30 -- -- 27 33 60 Kingston -- -- -- -- -- -- -- 24 18 42 -- -- 18 21 39 Saugerties -- -- -- -- -- -- -- 24 18 42 -- -- 7 15 22 Catskill -- -- -- -- -- -- -- 45 21 66 -- -- 9 15 24 Albany -- -- -- -- -- -- -- 40 30 70 -- -- 15 15 30 Total 36 28 113 114 291 51 39 256 210 556 51 39 229 276 595 3-Week Period from 16 MAY to 3 JUN 4-Week Period from 6 JUN to 1 JUL 13-Week Period from 11 JUL to 7 OCT Shoal Bottom Channel Shoal Bottom Channel Shoal Bottom Channel Region Sled Trawl Sled Trawl Total Sled Trawl Sled Trawl Total Sled Trawl Sled Trawl Total Battery -- -- 24 15 39 -- -- 24 20 44 -- -- 42 50 92 Yonkers 6 3 18 15 42 8 8 24 32 72 14 14 42 37 107 Tappan Zee 12 6 12 15 45 8 8 20 24 60 21 21 28 38 108 Croton-Haverstraw 12 6 12 15 45 12 8 24 28 72 21 21 28 36 106 Indian Point 6 6 18 39 69 12 8 20 68 108 21 21 28 33 103 West Point -- -- 21 51 72 -- -- 32 104 136 -- -- 28 33 61 Cornwall 9 6 24 18 57 8 8 48 52 116 14 14 21 26 75 Poughkeepsie -- -- 36 57 93 -- -- 28 64 92 -- -- 21 26 47 Hyde Park -- -- 21 33 54 -- -- 20 40 60 -- -- -- -- --
Kingston -- -- 12 18 30 -- -- 16 24 40 -- -- -- -- --
Saugerties -- -- 15 9 24 -- -- 16 8 24 -- -- -- -- --
Catskill -- -- 9 9 18 -- -- 12 12 24 -- -- -- -- --
Albany -- -- 9 9 18 -- -- 12 12 24 -- -- -- -- --
Total 45 27 231 303 606 48 40 296 488 872 91 91 238 279 699 NOTE: Dashes (--) indicate no sampling scheduled.
(Continued) 2005 Year Class Report
Table 2-3 (Continued) Summary of 2005 Sample Collection Information by River Region and Stratum for the Atlantic Croaker Ichthyoplankton Survey 4-Week Period from 14 NOV to 9 DEC Shoal Bottom Channel Region Sled Trawl Sled Trawl Total Battery -- -- 6 6 12 Yonkers 4 4 4 4 16 Tappan Zee 4 4 4 4 16 Croton-Haverstraw 2 2 2 2 8 Indian Point 4 4 4 4 16 West Point -- -- 4 4 8 Cornwall 2 2 2 2 8 Poughkeepsie -- -- -- -- --
Hyde Park -- -- -- -- --
Kingston -- -- -- -- --
Saugerties -- -- -- -- --
Catskill -- -- -- -- --
Albany -- -- -- -- --
Total 16 16 26 26 84 NOTE: Dashes (--) indicate no sampling scheduled.
2005 Year Class Report
Table 2-4 Specifications of Sampling Gear Used During the 2005 Longitudinal River Ichthyoplankton Survey 1.0-m2 Tucker Trawl Length 8.0 m Mouth (width) 1.0 m Mouth (height) 1.4 m Mesh size 500 m Net material Nytex (monofilament nylon)
Collection cup Length 30 cm Length with net-retaining ring 37 cm Mesh size 500 m Net material Nytex (monofilament nylon) 1.0-m2 Net Mounted on Epibenthic Sled Length 8.0 m Mouth (width) 1.0 m Mouth (height) 1.4 m Mesh size 500 m Net material Nytex (monofilament nylon)
Collection cup Length 30 cm Length with net-retaining ring 37 cm Mesh size 500 m Net material Nytex (monofilament nylon) 2005 Year Class Report
Table 2-5 Water Quality Sampling Locations During the 2005 Longitudinal River Ichthyoplankton, Atlantic Croaker Ichthyoplankton, and Fall Juvenile Surveys Scheduled Sampling Number of Water Quality Samples Scheduled Locations (RM) Per Region Per River Run LRS LRS LRS ACIS FJS River Region Shoals1 Channel River River River River River Runs Runs Runs Runs Runs 1-3 4-16 17-23 24-25 1-11 Battery -- 1, 3, 6, 9 12 12 12 12 12 Yonkers 19 12, 14, 17, 19, 22 19 19 19 20 19 Tappan Zee 29 25, 27, 29, 32 16 16 16 16 16 Croton- 36 35, 36, 37, 38 16 16 16 16 16 Haverstraw Indian Point 43 40, 42, 43, 46 16 16 16 16 16 West Point -- 49, 51, 53, 55 12 12 12 12 12 Cornwall 59 56, 57, 59, 61 16 16 16 15 16 Poughkeepsie -- 63, 67, 71, 75 -- 12 12 -- 12 Hyde Park -- 78, 80, 82, 84 -- 12 -- -- 12 Kingston -- 87, 89, 91, 93 -- 12 -- -- 12 Saugerties -- 96, 99, 102, 105 -- 12 -- -- 12 Catskill -- 109, 114, 118, -- 12 -- -- 12 122 Albany -- 126, 131, 135, -- 15 -- -- 15 138, 142 Total per 107 182 119 107 182 River Run NOTE: Dashes (--) indicate no sampling scheduled.
1 Sample collected from east and west shoals at designated river mile.
2005 Year Class Report
Table 2-6 Summary of 2005 Sample Analysis Information by River Region and Stratum for the Longitudinal River Ichthyoplankton Survey 3-Week Period from 14 MAR to 1 APR 3-Week Period from 4 APR to 22 APR 3-Week Period from 25 APR to 13 MAY Shoal Bottom Channel Shoal Bottom Channel Shoal Bottom Channel Region Sled Trawl Sled Trawl Total Sled Trawl Sled Trawl Total Sled Trawl Sled Trawl Total Battery -- -- 15 15 30 -- -- 12 9 21 -- -- 9 9 18 Yonkers 6 6 8 9 29 6 6 12 15 39 6 6 12 15 39 Tappan Zee 9 6 9 9 33 9 12 12 12 45 9 12 12 12 45 Croton-Haverstraw 9 6 9 9 33 12 9 12 12 45 12 9 12 12 45 Indian Point 6 6 9 9 30 6 6 12 12 36 6 6 9 15 36 West Point -- -- 15 15 30 -- -- 15 15 30 -- -- 9 9 18 Cornwall 6 4 12 12 34 9 6 9 9 33 9 6 12 15 42 Poughkeepsie -- -- -- -- -- -- -- 9 9 18 -- -- 15 15 30 Hyde Park -- -- -- -- -- -- -- 9 12 21 -- -- 15 18 33 Kingston -- -- -- -- -- -- -- 12 9 21 -- -- 9 12 21 Saugerties -- -- -- -- -- -- -- 12 9 21 -- -- 7 15 22 Catskill -- -- -- -- -- -- -- 9 12 21 -- -- 9 15 24 Albany -- -- -- -- -- -- -- 8 15 23 -- -- 15 15 30 Total 36 28 77 78 219 42 39 143 150 374 42 39 145 177 403 3-Week Period from 16 MAY to 3 JUN 4-Week Period from 6 JUN to 1 JUL 13-Week Period from 11 JUL to 7 OCT Shoal Bottom Channel Shoal Bottom Channel Shoal Bottom Channel Region Sled Trawl Sled Trawl Total Sled Trawl Sled Trawl Total Sled Trawl Sled Trawl Total Battery -- -- 12 12 24 -- -- 12 16 28 -- -- 21 21 42 Yonkers 6 3 9 12 30 8 8 12 16 44 14 14 21 28 77 Tappan Zee 12 6 12 12 42 8 8 20 20 56 14 21 28 28 91 Croton-Haverstraw 12 6 12 12 42 12 8 12 12 44 21 21 28 28 98 Indian Point 6 6 9 18 39 12 8 20 12 52 14 21 28 28 91 West Point -- -- 12 9 21 -- -- 16 20 36 -- -- 28 28 56 Cornwall 9 6 12 15 42 8 8 24 24 64 14 14 21 21 70 Poughkeepsie -- -- 18 12 30 -- -- 16 12 28 -- -- 21 21 42 Hyde Park -- -- 12 15 27 -- -- 20 20 40 -- -- -- -- --
Kingston -- -- 12 9 21 -- -- 16 12 28 -- -- -- -- --
Saugerties -- -- 15 9 24 -- -- 16 8 24 -- -- -- -- --
Catskill -- -- 9 9 18 -- -- 12 12 24 -- -- -- -- --
Albany -- -- 9 9 18 -- -- 12 12 24 -- -- -- -- --
Total 45 27 153 153 378 48 40 208 196 492 77 91 196 203 567 NOTE: Dashes (--) indicate no sampling scheduled.
(Continued) 2005 Year Class Report
Table 2-6 (Continued) Summary of 2005 Sample Analysis Information by River Region and Stratum for the Atlantic Croaker Ichthyoplankton Survey 4-Week Period from 14 NOV to 9 DEC Shoal Bottom Channel Region Sled Trawl Sled Trawl Total Battery -- -- 6 6 12 Yonkers 4 4 4 4 16 Tappan Zee 4 4 4 4 16 Croton-Haverstraw 2 2 2 2 8 Indian Point 4 4 4 4 16 West Point -- -- 4 4 8 Cornwall 2 2 2 2 8 Poughkeepsie -- -- -- -- --
Hyde Park -- -- -- -- --
Kingston -- -- -- -- --
Saugerties -- -- -- -- --
Catskill -- -- -- -- --
Albany -- -- -- -- --
Total 16 16 26 26 84 NOTE: Dashes (--) indicate no sampling scheduled.
2005 Year Class Report
Table 2-7 Summary of 2005 Sample Collection by River Region and Stratum for the Fall Juvenile Survey 15-Week Period from 4 JUL to 14 OCT 6-Week Period from 24 OCT to 2 DEC Shoal Bottom Channel Shoal Bottom Channel Region Beam Tucker Beam Tucker Total Beam Tucker Beam Tucker Total Battery -- -- 64 48 112 -- -- 36 -- 36 Yonkers 16 16 64 48 144 15 -- 33 -- 48 Tappan Zee 48 48 48 48 192 15 -- 24 -- 39 Croton-Haverstraw 40 40 48 48 176 15 -- 18 -- 33 Indian Point 32 32 55 56 175 15 -- 30 -- 45 West Point -- -- 80 97 177 -- -- 36 -- 36 Cornwall 39 40 48 48 175 15 -- 30 -- 45 Poughkeepsie -- -- 88 87 175 -- -- 30 -- 30 Hyde Park -- -- 64 48 112 -- -- 30 -- 30 Kingston -- -- 32 48 80 -- -- 24 -- 24 Saugerties -- -- 32 16 48 -- -- 30 -- 30 Catskill -- -- 24 24 48 -- -- 29 -- 29 Albany -- -- 32 32 64 -- -- 25 -- 25 Total 175 176 679 648 1678 75 -- 375 -- 450 NOTE: Dashes (--) indicate no sampling scheduled.
2005 Year Class Report
Table 2-8 Specifications of Sampling Gear Used During the 2005 Fall Juvenile Survey 1.0-m2 Tucker Trawl Length 8.0 m Mouth (width) 1.0 m Mesh size 3.0 mm Collection cage (codend)
Length 81 cm Diameter 41 cm Mesh size 3.0 mm 3.0-m Beam Trawl Length 7.6 m Beam width 3.0 m Net body 3.8-cm mesh (stretch)
Codend 3.2-cm mesh (stretch) net with 1.3-cm mesh (stretch) liner Hood 3.8-cm mesh (stretch)
Footrope Equipped with 5.1-cm rollers Headrope Equipped with three floats Mouth area 2.7 m2 2005 Year Class Report
Table 2-9 Specifications of Sampling Gear Used During the 2005 Beach Seine Survey 30.5-m Beach Seine Number of wings 2 Length of wings 12.0 m Depth of wings 2.4 m Wing mesh (bar) 1.0 cm Length of bag 6.1 m Depth of bag 3.0 m Bag mesh (bar) 0.5 cm Sampling area 450 m2 2005 Year Class Report
Table 2-10 Summary of 2005 Sample Collection by River Region for the Beach Seine Survey 5-Week Period from 13-Week Period from Region 13 JUN to 15 JUL 25 JUL to 21 OCT Total Yonkers 9 35 44 Tappan Zee 33 168 201 Croton-Haverstraw 21 98 119 Indian Point 9 35 44 West Point 9 35 44 Cornwall 9 42 51 Poughkeepsie 24 35 59 Hyde Park 24 35 59 Kingston 24 35 59 Saugerties 45 63 108 Catskill 57 70 127 Albany 36 49 85 Total 300 700 1000 2005 Year Class Report
Table 2-11 Stratum and Region Volumes (m3) and Surface Areas (m2) Used in Analysis of 2005 Hudson River Estuary Data Geographic Channel Bottom Shoal Region Shorezone Region Volume Volume Volume Volume Surface Area Battery 141,809,822 48,455,129 18,747,833 209,012,784 (a)
Yonkers 143,452,543 59,312,978 26,654,767 229,420,288 3,389,000 Tappan Zee 138,000,768 62,125,705 121,684,992 321,811,465 20,446,000 Croton-Haverstraw 61,309,016 32,517,633 53,910,105 147,736,754 12,101,000 Indian Point 162,269,471 33,418,632 12,648,163 208,336,266 4,147,000 West Point 178,830,022 25,977,862 2,647,885 207,455,769 1,186,000 Cornwall 94,882,267 36,768,629 8,140,123 139,791,019 4,793,000 Poughkeepsie 228,975,052 63,168,132 5,990,260 298,133,444 3,193,000 Hyde Park 131,165,041 32,012,000 2,307,625 165,484,666 558,000 Kingston 93,657,021 35,479,990 12,332,868 141,469,879 3,874,000 Saugerties 113,143,296 42,845,077 20,307,338 176,295,711 7,900,000 Catskill 83,924,081 42,281,206 34,526,456 160,731,743 8,854,000 Albany 32,025,080 13,517,183 25,606,842 71,149,105 6,114,000 Total 1,603,443,480 527,880,156 345,505,257 2,476,828,893 76,555,000
- a. Shorezone surface area is unknown and not used in data analysis as no beach seine sampling is performed in the Battery region.
2005 Year Class Report