Northeast Fisheries Science Center Reference Document 12-19

New England Harbor Porpoise

Bycatch Rates During 2010-2012 

Associated with Consequence Closure Areas 

by Christopher D. Orphanides
Northeast Fisheries Science Center Reference Document 12-19

US DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

National Marine Fisheries Service

Northeast Fisheries Science Center

Woods Hole, MA

September 2012

New England Harbor Porpoise

Bycatch Rates During 2010-2012

Associated with Consequence Closure Areas 

by Christopher D. Orphanides

National Oceanic Atmospheric Administration, National Marine Fisheries Service,

Northeast Fisheries Science Center, 166 Water Street, Woods Hole, MA, 02543 USA
Northeast Fisheries Science Center Reference Documents

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This document may be cited as:

Orphanides CD. 2012. New England harbor porpoise bycatch rates during 2010-2012 

associated with Consequence Closure Areas. US Dept Commer, Northeast Fish Sci 

Cent Ref Doc. 12-19; 15 p. Available from: National Marine Fisheries Service, 166 

Water Street, Woods Hole, MA 02543-1026, or online at http://www.nefsc.noaa.gov/

nefsc/publications/
ii 

TABLE OF CONTENTS 

Abstract ......................................................................................................................................................... 1 

Introduction ................................................................................................................................................... 1 

Methods ........................................................................................................................................................ 2 

Data ........................................................................................................................................................... 2 

Bycatch Rates ............................................................................................................................................ 3 

2011-2012 Pinger Compliance Rates........................................................................................................ 4

Results ........................................................................................................................................................... 5 

Discussion ..................................................................................................................................................... 6 

Acknowledgements ....................................................................................................................................... 7 

References Cited ........................................................................................................................................... 8 

LIST OF TABLES 

Table 1. Observed incidentally taken harbor porpoise, landings, trips, and percent Northeast 

Fishery Observer Program (NEFOP) groundfish trip landings by Consequence Closure Area 

(CCA)-associated-area in the New England gillnet fishery for the 2011-2012 HPTRP 

management season. ..................................................................................................................... 10 

Table 2. Bycatch rates, coefficients of variations (CVs), and hauls by Consequence Closure Area 

(CCA)-associated area in the New England gillnet fishery for the 2010-2011 (year 1), 2011-2012 

(year 2), and combined 2010-2012 Harbor Porpoise Take Reduction Plan (HPTRP) management 

seasons.........................................................................................................10 

Table 3. Estimated Harbor Porpoise Take Reduction Plan (HPTRP) pinger compliance in the 

New England gillnet fishery during the 2011-2012 HPTRP management season. ...................... 11

LIST OF FIGURES 

Figure 1. Harbor Porpoise Take Reduction Plan (HPTRP) New England gillnet management and 

closure areas. ................................................................................................................................. 12

Figure 2. Harbor Porpoise Take Reduction Plan (HPTRP) New England gillnet Consequence 

Closure Areas (CCAs). ................................................................................................................. 13

Figure 3. Northeast Fishery Observer Program (NEFOP) observed gillnet hauls and harbor 

porpoise bycatch locations for the 2011-2012 Harbor Porpoise Take Reduction Plan (HPTRP) 

management season.. .................................................................................................................... 14

Figure 4. At-Sea-Monitor (ASM) observed gillnet hauls and harbor porpoise bycatch locations 

for the 2011-2012 Harbor Porpoise Take Reduction Plan (HPTRP) management season.. ......... 15
1 

ABSTRACT 

The New England component of the Harbor Porpoise Take Reduction Plan (HPTRP) 

requires bycatch rates to be below HPTRP target bycatch rates in specified areas when averaged 

over two consecutive management seasons to avoid seasonal closure of Consequence Closure 

Areas (CCAs). Bycatch rates and HPTRP compliance rates were calculated for the Coastal Gulf 

of Maine (CGOM) and Southern New England (SNE) CCA-associated areas for the 2011-2012 

HPTRP management season and combined with previous estimates from the 2010-2011 season 

(Orphanides and Palka 2012). Bycatch rates (harbor porpoise per metric ton of landings) during 

the 2011-2012 season calculated using Northeast Fisheries Observer Program (NEFOP) data 

were 0.043 (CV=36%) in CGOM and 0.029 in SNE (CV=54%). The resulting two-year average 

bycatch rates (2010-2012) were 0.057 (CV=25%) in CGOM and 0.020 in SNE (CV=47%). 

These rates were above the target bycatch rate in CGOM (0.031) and below the target bycatch 

rate in SNE (0.023). For comparative purposes, bycatch rates were also calculated using a 

combination of At-Sea Monitor (ASM) data, a data source which began in 2010, and the 

traditionally used NEFOP data. Joint 2011-2012 NEFOP-ASM bycatch rates were 0.038 (CV= 

23%) for CGOM and 0.035 (CV= 46%) for SNE, resulting in two-year bycatch rates of 0.053 

(CV= 14%) in CGOM and 0.042 (CV= 32%) in SNE. Compliance with HPTRP pinger 

regulations was also evaluated. HPTRP pinger compliance (pingers fully deployed and all fully 

functional) was estimated to be 62.0% in CGOM and 73.2% in SNE. 

INTRODUCTION 

Since the creation of the Northeast Fisheries Science Center (NEFSC) Northeast Fishery 

Observer Program (NEFOP) in 1989, harbor porpoise bycatch has been the focus of much 

attention due to frequently observed incidental takes in commercial gillnet fisheries. In response 

to high levels of observed harbor porpoise incidental mortality and serious injury, Harbor 

Porpoise Take Reduction Teams (HPTRTs) were convened for the Gulf of Maine in 1996 and 

for the Mid-Atlantic in 1997, and were reconvened for both regions combined in 2007. As a 

result of reconvening the HPTRT in 2007, on February 19, 2010 NMFS published the 2010 

HPTRP (75 FR 7383) to address both non-compliance with existing HPTRP requirements and 

bycatch that was occurring outside of existing HPTRP management areas. One of the key new 

components in the 2010 HPTRP that was developed to address non-compliance in areas with 

historically high levels of bycatch was the Consequence Closure Area (CCA) strategy. This 

strategy involves three potential seasonal closure areas, which are referred to as CCAs. Under 

this strategy, if the average bycatch rate within two consecutive management seasons in a “CCAassociated area” exceeds a specified target bycatch rate, then a seasonal closure of the CCA is 

triggered. These target bycatch rates were set to match previously observed bycatch rates within 

CCA-associated areas on NEFOP-observed hauls with full pinger deployment that were 

observed between January 1, 1999 and May 31, 2007 (Palka and Orphanides, 2008). 

CCA-associated areas encompass CCAs and are composed of existing Management 

Areas (MAs). The Coastal Gulf of Maine (CGOM) CCA-associated area is composed of the 

Mid-Coast, Stellwagen Bank, and Massachusetts Bay MAs (Figure 1), which also include the 

CGOM CCA (Figure 2). The target bycatch rate for the CGOM CCA-associated area is 0.031 

harbor porpoise per metric ton of landings; if that rate is exceeded after two consecutive 

management seasons, the CGOM CCA becomes seasonally closed under the 2010 HPTRP. The 
2 

Southern New England (SNE) CCA-associated area is the Southern New England MA (Figure 

1), which includes the Eastern Cape Cod CCA and the Cape Cod South Expansion CCA (Figure 

2). The target bycatch rate for the SNE CCA is 0.023 harbor porpoise per metric ton of landings, 

and if that rate is exceeded after two consecutive management seasons, both the Eastern Cape 

Cod and Cape Cod South Expansion CCAs become seasonally closed. For details on the time 

period each MA is either seasonally closed to gillnet fishing or requires the use of pingers, see 

Figure 1. 

The first management season under the 2010 HPTRP CCA strategy was the 2010-2011 

HPTRP management season, which was from Sept 15, 2010 to May 31, 2011. CCA bycatch 

rates and compliance with the pinger requirements for that season were documented in 

Orphanides and Palka (2012). The current report provides a similar update for the second 

HPTRP management season (Sept 15, 2011 to May 31, 2012). This report also provides the first 

two-year average bycatch rates for each CCA. 

METHODS 

Data 

The NEFOP data and At-Sea-Monitor (ASM) data were used to calculate bycatch and 

compliance rates. The NEFSC NEFOP was initiated in 1989 to document the bycatch of marine 

mammals taken incidentally in commercial fishing operations (Waring et al. 2004). Its role has 

since expanded to monitor commercial fishing from Maine through North Carolina, collecting, 

maintaining, and distributing data for scientific and management purposes. To achieve these and 

other goals, NEFOP collects data on landed and discarded catch, numerous fishing vessel and 

gear characteristics, and many other variables. For additional details on the data collected, see 

the NEFOP Fisheries Observer Program Manual for 2010 at http://www.nefsc.noaa.gov/fsb. 

The ASM program was established in response to Amendment 16 of the Northeast 

Multispecies Fishery Management Plan (FMP) to monitor catch and discards in the large mesh 

portion of this fishery, often referred to as the “groundfish” fishery. Specifically, ASM data are 

used to monitor Annual Catch Entitlements (ACE) and Annual Catch Limits (ACL) of each 

stock managed by the FMP as of May 1, 2010 and to verify area fished as well as catch and 

discards by species and gear type (NOAA Fisheries 2011, 15 CFR Part 902, 50 CFR Part 648). 

When using the ASM data for calculating harbor porpoise bycatch rates, care was taken to 

combine the ASM data with NEFOP data in a manner that ensured the final sample was 

representative of the groundfish/non-groundfish (i.e., Northeast Multispecies fishery/other 

fisheries) distribution in the NEFOP data (see Bycatch Rates section of the Methods below for 

more details). For complete information on the fields collected in ASM see the ASM Program 

Manual at http://www.nefsc.noaa.gov/fsb, and for additional background on ASM data and the 

relationship between NEFOP and ASM data see Orphanides and Palka (2012). 

The 2011-2012 datasets (NEFOP and ASM) were processed using standard protocols 

established for past bycatch and compliance calculations (e.g., Orphanides 2011; Orphanides and 

Palka 2012). Specifically, the 2011-2012 recorded dressed landed weights were converted to live 

weights using established conversion factors (Warden and Orphanides 2008; Palmer 2010) and 

rare missing location values were imputed using medians from representative strata using 

methods described in Warden and Orphanides (2008). For the 2011-2012 data, original location 

values were present in over 99% of SNE and CGOM hauls, and no incidental harbor porpoise 

takes were associated with imputed locations in CCA-associated areas. One NEFOP haul was 
3 

located on the border of the SNE and Massachusetts Bay MAs. This haul was counted as only 

being located in the SNE MA since most other hauls on that trip occurred in the SNE MA and 

none occurred in the Massachusetts Bay MA. 

Bycatch Rates 

Bycatch rates were calculated as the number of observed harbor porpoise incidental takes 

per observed metric tons (mtons) of live fish landed. All bycatch rates discussed in this report 

can be assumed to be in terms of harbor porpoise incidental takes per metric tons of live fish 

landed. A harbor porpoise incidental take was defined as any observed incidentally caught harbor 

porpoise that was recorded as either alive or dead. In some cases, it was possible that a 

decomposed harbor porpoise could be an animal that was dead prior to being entangled in a 

gillnet. Therefore, if an incidental take was recorded as being either moderately or severely 

decomposed when incidentally caught, the gear’s soak duration was examined to see if the 

incidental take could have reached the recorded state of decomposition within the given soak 

time, i.e., whether the harbor porpoise could have been alive when entangled in the net. No 

harbor porpoise were excluded due to decomposition status in the 2011-2012 season. 

When calculating bycatch rates using only the NEFOP data (NEFOP	Bycେେ୅ሻ, the number 

of harbor porpoise observed incidentally taken in a CCA associated time-area (NEFOP Observed 

TakesCCA) was divided by the amount of effort (metric tons of live fish landed) in the 

corresponding CCA associated time-area (NEFOP Observed EffortCCA): 

NEFOP	Bycେେ୅ ൌ 	 NEFOP	Observed	Takesେେ୅	/	NEFOP	Observed	Effort	େେ୅	

Calculating bycatch rates using NEFOP and ASM data (Joint NEFOP ASM BycCCA) was 

slightly more complicated because it was necessary to account for the fact that the ASM data 

were the result of a higher observer coverage as compared to the NEFOP data and the ASM data 

were only recorded from groundfish trips: 

Joint	NEFOP	ASM	Bycେେ୅ ൌ

ሺGroundβish%େେ୅	 ∗ 	GroundβishBycେେ୅	ሻ 	൅ 		 ሺNonGroundβish%େେ୅	 ∗ 	NonGroundβishBycେେ୅	ሻ					

The ASM data are by definition a subset of the entire gillnet fishery as it is designed to 

only sample groundfish trips. In contrast, the NEFOP data are designed to be a sample of the 

entire gillnet fishery. When calculating the joint NEFOP-ASM bycatch rates, NEFOP data were 

separated into groundfish and non-groundfish trip types using the NEFOP sector id code (NOAA 

Fisheries 2010). The NEFOP groundfish trips were then pooled with the ASM groundfish trips 

and used to calculate a groundfish bycatch rate for each CCA associated time-area 

(GroundfishBycCCA). Similarly, non-groundfish NEFOP data were used to calculate a nongroundfish bycatch rate for each CCA associated time-area (NonGroundfishBycCCA). Next, steps 

were taken to preserve the groundfish/non-groundfish ratio of the NEFOP data and retain 

consistency with how the target bycatch rates were originally calculated from only NEFOP data. 

The percentage of landings from the two trip types (groundfish and non-groundfish) was 

recorded for each CCA associated time-area (Groundfish%CCA and NonGroundfish% CCA). These 

percentages were then used to weight the groundfish and non-groundfish bycatch rates. Thus, the 

weighted groundfish bycatch rate had an influence proportional to the percentage of groundfish 

trip landings in the NEFOP data. 
4 

Once the NEFOP-only and joint NEFOP-ASM bycatch rates for 2010-2011 and 2011-

2012 HPTRP management seasons were calculated, two-year average bycatch rates were 

calculated using a weighted average of the estimates from those two management seasons, or 

“years,” as described in Palka and Orphanides (2008). The two year average is weighted by the 

number of observed hauls in each HPTRP management season. 

2	Yr	Weighted	Avg	Byc	Rate ൌ

Yr1	Byc	Rate ∗ Yr1	N	of	Obs	Hauls ൅ 	Yr2	Byc	Rate ∗ Yr2	N	of	Obs	Hauls

Yr1	Observed	Hauls ൅ Yr2	Observed	Hauls

For both the NEFOP-only bycatch rates and the joint NEFOP-ASM bycatch rates, the 

number of observed hauls in the NEFOP data was used to weight the two year average. For the 

joint NEFOP-ASM two-year bycatch rates, weighting with only NEFOP hauls was done to keep 

the ASM groundfish hauls from having a disproportionate influence on the final bycatch rates. 

Standard bootstrapping techniques were used to derive the coefficients of variation (CV) 

and 95% confidence intervals (CIs) for the bycatch estimates for each 2011-2012 stratum, as has 

been done for past bycatch estimates (e.g., Orphanides and Palka 2012). Also consistent with 

past estimates, the re-sampling unit used was an entire trip rather than an individual haul to 

ensure that any trip-based characteristics that might influence bycatch rates were carried over 

into the estimated CV (Bisack 2003). The two HPTRP season bycatch rates and their associated 

CVs were used to derive the two-year bycatch rate CVs using the following equation: 

CV	ሺ2	Yr	Weighted	Avg	Byc	Rateሻ ൌ

ඥሺሺYr1	Weightଶሻ ∗ varሺYr1	Byc	Rateሻሻ ൅ ሺሺYr2	Weightଶሻ ∗ varሺYr2	Byc	Rateሻሻ

2	Yr	Weighted	Avg	Byc	Rate

where 

Yr1	Weight ൌ 	

Yr1	N	Obs	Hauls

Yr1	N	Obs	Hauls ൅ Yr2	N	Obs	Hauls

Yr2	Weight ൌ 	

Yr2	N	Obs	Hauls

Yr1	N	Obs	Hauls ൅ Yr2	N	Obs	Hauls

and 

varሺYr1	Byc	Rateሻ ൌ ሺYr1	Byc	Rate ∗ CVሺYr1	Byc	Rateሻሻଶ

varሺYr2	Byc	Rateሻ ൌ ሺYr2	Byc	Rate ∗ CVሺYr2	Byc	Rateሻሻଶ

2011-2012 Pinger Compliance Rates 

During times and areas where pingers are required in the New England gillnet fisheries, 

the 2010 HPTRP requires that each gillnet string has one functioning pinger on each end of the 

string, and one functioning pinger in between each net. For example, a typical gillnet string with 
5 

10 300-foot long nets is required to have 11 functioning pingers on the string. In the past, the 

measure of compliance was often calculated based only on whether a gillnet haul had the proper 

number of pingers on the string because the functionality of the pingers was not regularly 

recorded by NEFOP (Palka et al. 2008, Orphanides et al. 2009). Use of the proper number of 

pingers on a string, regardless of whether the pinger is working, will be referred to here as full 

pinger deployment. 

Recently, NEFOP developed a new pinger tester that was deployed on a limited sample 

of NEFOP trips during 2011 and 2012 (none deployed on ASM trips). On those trips, the aim 

was to test all of the pingers on each string to determine if they were functioning properly. Pinger 

tester data from hauls with full pinger deployment were used to assess the true pinger 

compliance rate; that is, the number of tested hauls with both full pinger deployment and all 

pingers functional were divided by the number of tested hauls with full pinger deployment. The 

resulting number was the percent of hauls with fully deployed pingers that also had all pingers 

functioning. This percentage was then applied to the percentage of all NEFOP observed hauls 

with full pinger deployment (whether tested for pinger functionality or not) to estimate the true 

pinger compliance rate. For additional details on how pinger tester data were recorded, see 

Orphanides and Palka (2012). Compliance with HPTRP pinger regulations was assessed using 

only NEFOP data to be consistent with the previous year’s CCA analysis (Orphanides and Palka 

2012), and because pinger tester data were only collected on NEFOP hauls. However, full pinger 

deployment was also summarized for ASM data. 

RESULTS 

The spatial distributions of the observed hauls and harbor porpoise takes collected by the 

NEFOP and ASM programs are similar (Figures 3 and 4). Between the NEFOP and ASM data 

21 harbor porpoise were observed incidentally taken in CGOM CCA-associated areas and 8 were 

observed incidentally taken in SNE (Table 1). In CGOM the observed bycatch rates were above 

the target bycatch rate (0.031) in all cases (Table 2). The 2011-2012 CGOM bycatch rate was 

above the target when using NEFOP data (0.043, CV=36%) and when using the joint NEFOPASM data (0.038, CV=23%). The larger sample size of observed hauls in the joint NEFOP-ASM 

bycatch rate resulted in an increased level of confidence, and a lower CV. The two-year 

weighted average bycatch rates were also above the targets: 0.057 (CV=25%) for NEFOP and 

0.053 for NEFOP-ASM (CV=14%) (Table 2). 

In the 2011-2012 season, the SNE observed bycatch rates (0.029 for NEFOP, CV=54%, 

and 0.035 for NEFOP-ASM, CV = 46%) were above the SNE target bycatch rate (0.023) (Table 

2). However, the two-year weighted average bycatch rate for SNE was below the target bycatch 

rate when using NEFOP data (0.020, CV = 47%) and above the target when using joint NEFOPASM data (0.042, CV=32%). 

Compliance with pinger regulations was estimated at 62% in CGOM and 73% in SNE. 

Full pinger deployment occurred on 80% of observed hauls in CGOM and 73% of hauls in SNE 

(Table 3). However, among CGOM hauls with full pinger deployment also tested for pinger 

functionality, about 23% did not have all pingers functioning. In SNE all tested pingers on hauls 

with full pinger deployment were functional, though the sample size was much smaller than in 

CGOM. 
6 

DISCUSSION 

In this paper two sets of CCA bycatch rates were calculated. One set was calculated using 

only NEFOP data, and the other set was calculated using both NEFOP and ASM data. For the 

2010-2011 HPTRP season, NOAA Fisheries Northeast Regional Office (NERO) decided to use 

NEFOP bycatch rates to evaluate bycatch rates within CCA-associated areas in order to maintain 

consistency with how the original CCA target bycatch rates were calculated. Compared to the 

2010-2011 HPTRP season, the NEFOP 2011-2012 bycatch rates were lower in CGOM, but 

higher in SNE. Based on year one CCA data (2010-2011), it was determined that the bycatch rate 

in the CGOM CCA was too high to avoid a closure even if no harbor porpoise were caught in 

year two (2011-2012). This assertion proved correct, as the combined NEFOP two-year average 

bycatch rate was 0.057 (CV=25%) in CGOM, well above the 0.031 target. The corresponding 

two-year average bycatch rate in SNE was 0.020 (CV=47%), slightly below the target rate of 

0.023. 

In CGOM, the two-year bycatch rates were very comparable when calculated using 

NEFOP data (0.057, CV=25%) and when using joint NEFOP-ASM data (0.053, CV=14%). 

However, in SNE the two-year bycatch rates differed greatly between NEFOP data (0.020, 

CV=47%) and joint NEFOP-ASM data (0.042, 32%). The difference in rates between data 

sources is likely associated with sample size combined with the variability of observing a rare 

event like an incidental harbor porpoise take. The sample size of observed hauls (and landings) 

in SNE was smaller than in CGOM, whether looking at NEFOP, ASM, or joint datasets (Tables 

1 and 2). Further, the sample size of hauls (and landings) in NEFOP data in SNE was much 

smaller than the sample size of ASM data in the region. Differences in the vessels sampled and 

their manner of fishing between NEFOP and ASM data could also contribute to the differences 

between these rates. An investigation comparing NEFOP and ASM data is currently underway. 

The two-year bycatch rates calculated using joint NEFOP-ASM data were weighted 

using only the NEFOP hauls, though one might expect that both NEFOP and ASM hauls would 

be used to weight this bycatch rate. In this case, only NEFOP hauls were used so that the ASM 

groundfish hauls would not have a disproportionate effect on the final bycatch rates. However, 

one could argue that since ASM hauls were used to calculate the single-year bycatch rates, they 

should be used for the two-year rates as well. The best solution may be to use, but somehow 

down-weight, the number of ASM hauls in the weighting process when calculating the two-year 

average bycatch rate. But, in practice, weighting the two-year bycatch rate using both the ASM 

and NEFOP hauls made little difference in either the final two-year bycatch rate or CV. In a 

post-hoc analysis using both NEFOP and ASM hauls to weight the two-year bycatch rates, the 

CVs of neither region differed from when only NEFOP hauls were used to weight the two-year 

bycatch rates, and the bycatch rates shifted from 0.057 to 0.054 in CGOM and 0.040 to 0.042 in 

SNE. 

It is possible that the high two-year bycatch rate in CGOM was due, at least in part, to a 

mixture of working and non-working pingers on the hauls with fully deployed pingers. Research 

in this fishery has shown that bycatch rates for hauls without pingers has been two to three times 

the rates of hauls with pingers (Palka et al. 2008). In addition, that study showed that hauls with 

insufficient numbers of pingers can have higher bycatch rates than hauls with the required 

number of pingers; however, the reason for this is not clear. Pinger functionality analysis found 

that roughly 80% of hauls in 2011-2012 with fully deployed pingers that were tested for 

functionality had all pingers functioning, compared to roughly 62% in 2010-2011 (Orphanides 
7 

and Palka 2012). The problem of non-functioning pingers has been consistent throughout this 

fishery, and it makes it challenging to assess the true capability of pingers to deter harbor 

porpoise within this fishery (Palka et al. 2008, Orphanides et al. 2009, Orphanides et al. 2010, 

Orphanides and Palka 2012). Other possible reasons for high bycatch rates may include shifts in 

fishing effort or harbor porpoise distributions, though these have not been investigated in this 

report. The most likely cause of high bycatch rates in CGOM is the low pinger compliance rates, 

though more data is needed to confirm the effect of missing or non-functional pingers on a 

string. 

ACKNOWLEDGEMENTS 

Special thanks to the NEFOP and ASM observers whose data make this analysis possible. 

Also, much gratitude is due to several NEFOP and DMS staff members who sped the processing 

of the NEFOP gillnet data in order to help get this paper published as quickly as possible. Thanks 

to Joshua Hatch for assistance preparing the data used in this analysis. Lastly, thanks to 

anonymous staff members at the NEFSC for their reviews and comments on this paper. 
8 

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pinger regulations for the Northeast gillnet fishery. US Dept Commer, Northeast Fish Sci 

Cent Ref Doc. 08-10; 13 p., 166 Water Street, Woods Hole, MA 02543-1026, or online 

at http://www.nefsc.noaa.gov/nefsc/publications/
9 

Palka DL, Rossman, MC, VanAtten, AS, and CD Orphanides. 2008. Effect of pingers on harbour 

porpoise bycatch in the US northeast gillnet fishery. J. Cetacean Res. Manage. 10(3):217-

226. 

Palmer MC. 2010. A standard method to apportion groundfish catch to stock area for the purpose 

of real time quota monitoring under Amendment 16. US Dept Commer, Northeast Fish 

Sci Cent Ref Doc. 10-02; 32 p. Available from: National Marine Fisheries Service, 166 

Water Street, Woods Hole, MA 02543-1026, or online 

at http://nefsc.noaa.gov/publications/. 

Warden ML, Orphanides CD. 2008. Preparation of the Northeast Fisheries Observer Program 

gillnet data for use in bycatch analyses of protected species. US Dept Commer, Northeast 

Fish Sci Cent Ref Doc. 08-17; 44 p. Available from: National Marine Fisheries Service, 

166 Water Street, Woods Hole, MA 02543-1026 

or http://www.nefsc.noaa.gov/publications/ 

Waring GT, Pace RM, Quintal JM, Fairfield CP, Maze-Foley K, Editors. 2004. US Atlantic and 

Gulf of Mexico marine mammal stock assessments -- 2003. US Dep Commer, NOAA 

Tech Memo NMFS NE 182; 287 p. Available from: NOAA Fisheries, 166 Water St, 

Woods Hole MA 02543-1026 or http://www.nefsc.noaa.gov/nefsc/publications/
10 

Table 1. Observed incidentally taken harbor porpoise, landings, trips, and percent Northeast Fishery Observer Progroundfish trip landings by Consequence Closure Area (CCA)-associated-area in the New England gillnet fishery f

HPTRP management season. 

Table 2. Bycatch rates, coefficients of variations (CVs), and hauls by Consequence Closure Area (CCA)-associated 

England gillnet fishery for the 2010-2011 (year 1), 2011-2012 (year 2), and combined 2010-2012 Harbor Porpoise Ta

(HPTRP) management seasons. 

CCA‐Associated Area

G

NEFOP ASM NEFOP ASM NEFOP ASM

Coastal Gulf of Maine 8 (8) 13 (13) 277 741 188.12 (187.21) 437.64 (437.64) 

Southern New England 3 (0) 5 (5) 37 175 104.60 (62.78) 361.52 (361.52) 

Total Harbor Porpoise

(harbor porpoise on

groundfish hauls)

Total Landings in mtons

Total Trips (groundfish landings in mtons)

CCA‐Associated Area Data Source(s)

Year 1 Bycatch rate(CV, Observed Hauls)

Year 2 Bycatch Rate(CV, Observed Hauls)

2‐Year Weigh

Average Byca

Rate (CV)

Coastal Gulf of Maine NEFOP 0.078 (34%, 883) 0.043 (36%, 1265) 0.057 (25%

Coastal Gulf of Maine NEFOP‐ASM 0.074 (18%, 2589) 0.038 (23%, 3339) 0.053 (14%

Southern New England NEFOP 0.012 (96%, 238) 0.029 (54%, 205) 0.020 (47%

Southern New England NEFOP‐ASM 0.048 (43%, 651) 0.035 (46%, 925) 0.042 (32%
11 

Table 3. Estimated Harbor Porpoise Take Reduction Plan (HPTRP) pinger compliance in the New England gillnet fi2012 HPTRP management season. 

CCA‐Associated Area

Data

Source

Full pinger

deployment hauls

Non‐Full Pinger

Deployment Hauls

Total Observed

Hauls

Full Pinger

Deployment

Percentage

Recorded Hauls (and

Trips) Tested for

Pinger Functionality

Full Pinger Deployment

Hauls (and Trips) Tested

for Pinger Functionality

Functi

Full 

Deploy

Coastal Gulf of Maine NEFOP 1012 253 1265 80.00% 214 (56) 120 (38) 77

Coastal Gulf of Maine ASM 1647 427 2074 79.41% 0 0 

Southern New England NEFOP 150 55 205 73.17% 12 (3) 10 (3) 10

Southern New England ASM 578 142 720 80.28% 0 0 
12 

Figure 1. Harbor Porpoise Take Reduction Plan (HPTRP) New England gillnet management and 

closure areas. 
13 

Figure 2. Harbor Porpoise Take Reduction Plan (HPTRP) New England gillnet Consequence 

Closure Areas (CCAs). 

 
14 

Figure 3. Northeast Fishery Observer Program (NEFOP) observed gillnet hauls and harbor 

porpoise bycatch locations for the 2011-2012 Harbor Porpoise Take Reduction Plan (HPTRP) 

management season. Hatched area represents the year-round Western Gulf of Maine Closure Area 

under the Northeast Multispecies Fishery Management Plan (FMP). For a corresponding figure for 

the 2010-2011 season, see Orphanides and Palka (2012). 

 
15 

Figure 4. At-Sea-Monitor (ASM) observed gillnet hauls and harbor porpoise bycatch locations for 

the 2011-2012 Harbor Porpoise Take Reduction Plan (HPTRP) management season. Hatched area 

represents the year-round Western Gulf of Maine Closure Area under the Northeast Multispecies 

Fishery Management Plan (FMP). For a corresponding figure for the 2010-2011 season, see 

Orphanides and Palka (2012). 
Procedures for Issuing Manuscripts

in the

Northeast Fisheries Science Center Reference Document (CRD) Series

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All manuscripts submitted for issuance as CRDs 

must have cleared the NEFSC’s manuscript/abstract/

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Publications and Reports

of the

Northeast Fisheries Science Center

The mission of NOAA’s National Marine Fisheries Service (NMFS) is “stewardship of living marine resources 

for the benefit of the nation through their science-based conservation and management and promotion of the 

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Science Center (NEFSC) supports the NMFS mission by “conducting ecosystem-based research and assessments of living marine resources, with a focus on the Northeast Shelf, to promote the recovery and long-term 

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Results of NEFSC research are largely reported in primary scientific media (e.g., anonymously-peer-reviewed 

scientific journals). However, to assist itself in providing data, information, and advice to its constituents, the 

NEFSC occasionally releases its results in its own media. Currently, there are three such media:

NOAA Technical Memorandum NMFS-NE -- This series is issued irregularly. The series typically includes: data reports of 

long-term field or lab studies of important species or habitats; synthesis reports for important species or habitats; annual reports 

of overall assessment or monitoring programs; manuals describing program-wide surveying or experimental techniques; literature 

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most issues receive copy editing.

Resource Survey Report (formerly Fishermen’s Report) -- This information report is a regularly-issued, quick-turnaround report on 

the distribution and relative abundance of selected living marine resources as derived from each of the NEFSC’s periodic research vessel surveys of the Northeast’s continental shelf. This report undergoes internal review, but receives no technical or copy editing.

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on “Reports and Publications” (http://www.nefsc.noaa.gov/nefsc/publications/). To access Resource Survey Report, consult the Ecosystem 

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