When to kill or release Marlin??

[Bluewater Sportfishing]

The release of White, Blue, and Striped Marlin.


I read a while back about the catch and release of 179 Striped Marlin. I said to myself, “wow, what an accomplishment!” That is quite a day of fishing. After much thought I asked myself “I wonder how many of those fish lived after the release. Now I don’t mean did they swim away “looking healthy.” I mean in a week’s time did they die? Were they bleeding from the gills or mouth heavily, but yet still swam off looking healthy. I ask this for one reason. I see pics of people holding whites and stripies along with sailfish that are bleeding badly from the gills or mouth and they say this fish was released unharmed. This makes me laugh as the fish is clearly harmed and may not live. So I ask why not just kill the fish and eat it. For the record Marlin is a very tasty fish. If you take the fish aboard and handle it for a pic, you are removing the slime coat from the fish, thus removing the fish’s natural ability to ward off infection, especially if your hands or gloves are dry. All those hooks that were left in the 179 striped marlin, could they infect the fish and cause it to die? Are we really practicing conservation or fishing for bragging rights thinking we are conserving the fish we hold so dear to us all?


Blue Marlin are a little different as they are bigger and you cant bring a 400 pounder in the boat to take a pic and release it. On the other hand if the fish puked up its belly why wouldn’t you kill the fish and eat it? What if the bait and hook were in the gills and bleeding? Would you try to release it or kill it? Kill the damn thing its gonna die anyway!
Same thing if the hook was imbedded in the bill, wont that cause infection and the fish dies a week or two later? I like to conserve as much as the next person but sometimes the right thing to do may, at the time feel like the wrong thing to do.

I don’t want to come off as a tree hugger but I would rather see a Marlin on the dinner plate feeding people then sinking to the bottom and feeding the crabs.
Just food for thought.

[Tuna Taxi]

I don't know if you'll find an answer to your question because it is a personal choice for each person in each situation. Of course, you can be making the cirrect choice for you at the moment, and still be judged by those who believe their moral values are superior to yours. Just do what you feel is right.

As for releasing them, I don't know if we will ever know how hard it is on a fish when they are released bleeding a little, worn out, and maybe a little bruised from the haul-out and photo op. All I know is that in my younger days I wised off to the wrong person in a bar a few times, and each time I was "released" bleeding, worn out, and bruised.......but I made it.

[POON MAN]

Sharks need a free meal too

I wish somebody had the real answer , I think that the only way that you could count the mortality rate is to put an electronic tag in each fish and see what happens ???

Has any organization attempted this yet ?

I bet we would be surprised at the results and i would guess it would not be all that great just MHO

[giggyfish]

In my opinion you should never have to apologize for killing a fish intended for your table whether it is a 12" brook trout or a 1000 lb marlin as long as you practice legal and ethical limits and do not waste any portion of your catch. Senseless laws or beliefs that require you to throw back a gill raked fish should be avoided. It does no one any good. And for those that think catch and release is the end all be all need to find a new hobby and stop torturing fish. I will apologize to no one for keeping any species of fish because I know that for every fish that ends up on my barbeque one hundred swam to fight again.

USE COMMON SENSE AND FIND A GOOD MARINADE.

[FASTWATER]

A gentleman in Ixtapa-Zihue. named Ed Kunze summed it up the best for me a marlin swimming off bleeding or a hook in his mouth has a lot better chance of living than one dead on the floor boards !!!PEACE

[Deep C]

Its hard to say what fish will make it and which wont. I have tagged and released fish in tournaments that I thought would be crab food in no time only to get a tag return from some portuguese long liner or Cozumel charter boat thousands of miles away years later. I have seen what appeared to be healthy ones get released only to have a diver a couple days after the tourney say there were a bunch on the bottom.
Blood doesn't spell the end to me. Hell I spill a quart every time I get creative in the engine room.
A fish whos color won't come back after attempts to revive is usually my signal. We go long doing a revival. We had a fish at Chub last year that bled like a stuck pig. Only a small tear in the mouth. Took ten minutes or so but the color came all the way back and it swam off happy. Did he make it? I can't say for sure but it did go from looking like crap to bright and tlit back up at let go time...
I'm a firm believer that they stand a far better chance of surving even if bad looking in the water than in the pit of my boat. That is not saying that there havn't been ones I knew were gonners and made their way to the smoker but those ones are very rare indeed.
Does a J rip their guts out? Does a circle impact jaws causing starvation? Both may be true or not... I don't have the answer...

[SAXIS ISLANDER]

Virginia runs a pretty good tagging program and I was an avid participant years ago. Mortality rate was too high and tag return too lowon tagged grey trout for it to continue with that species.

Tagged a small cobia and was pretty sure that I had severed the spinal cord with the insertion of the tag. The fish went straight down with no movement as it was released. Tag was retreived by a commercial fisherman off MHC two years later. Just goes to show that you never know.

Keeping a fish is a personal choice. My stance is this. If you want to legally keep it do it with 100% conviction and defend your stance with vigor. If there is any doubt as to what to do...let it go. Boated fish have a 0% survival rate.

[Finnseeker]

The release of White, Blue, and Striped Marlin.


I read a while back about the catch and release of 179 Striped Marlin. I said to myself, “wow, what an accomplishment!” That is quite a day of fishing. After much thought I asked myself “I wonder how many of those fish lived after the release. Now I don’t mean did they swim away “looking healthy.” I mean in a week’s time did they die? Were they bleeding from the gills or mouth heavily, but yet still swam off looking healthy. I ask this for one reason. I see pics of people holding whites and stripies along with sailfish that are bleeding badly from the gills or mouth and they say this fish was released unharmed. This makes me laugh as the fish is clearly harmed and may not live. So I ask why not just kill the fish and eat it. For the record Marlin is a very tasty fish. If you take the fish aboard and handle it for a pic, you are removing the slime coat from the fish, thus removing the fish’s natural ability to ward off infection, especially if your hands or gloves are dry. All those hooks that were left in the 179 striped marlin, could they infect the fish and cause it to die? Are we really practicing conservation or fishing for bragging rights thinking we are conserving the fish we hold so dear to us all?


Blue Marlin are a little different as they are bigger and you cant bring a 400 pounder in the boat to take a pic and release it. On the other hand if the fish puked up its belly why wouldn’t you kill the fish and eat it? What if the bait and hook were in the gills and bleeding? Would you try to release it or kill it? Kill the damn thing its gonna die anyway!
Same thing if the hook was imbedded in the bill, wont that cause infection and the fish dies a week or two later? I like to conserve as much as the next person but sometimes the right thing to do may, at the time feel like the wrong thing to do.

I don’t want to come off as a tree hugger but I would rather see a Marlin on the dinner plate feeding people then sinking to the bottom and feeding the crabs.
Just food for thought.

Firstly thanks for the post and secondly some info.
Every single fish we hooked were in the corner of the mouth and there were no bleeeding fish or gut hooked fish as with a J hook. The underwater camera's all show not a single fish bleeding and all fish hooked in the corner of the mouth.

Secondly the release times were less than a minute in some instances so lactic acid build up did not occur nor did we put preassure on the fish to stress them out with long fight times which would tire a fish and make it venerable to heart attacks, predators etc. The fish were very hot and green when released.

Thirdly the Eagle claw light wire hook we use rusts out and falls out the corner of the mouth in a day or 3 according to Eagle Claw study.
I have attached the study to back up and support some of this.

About taking marlin out the water holding them up for photo's and damaging their gills etc while you take a picture , this should not be done as it harms the fish. The fish and photo should be in the water swimming alongside the boat in the water and released as quick as possible with less harm and trauma to the fish.

1
A COMPARISON OF CIRCLE HOOK AND “J” HOOK PERFORMANCE IN
RECREATIONAL CATCH AND RELEASE FISHERIES FOR BILLFISH
by
Eric D. Prince, Mauricio Ortiz, and Arietta Venizelos
National Marine Fisheries Service
Southeast Fisheries Science Center
http://www.sefsc.noaa.gov/
75 Virginia Beach Drive
Miami, FL 33149
eric.prince@noaa.gov, (305) 361-4248
Originally Published and Copyrighted
byAmerican Fisheries Society (AFS)
http://www.fisheries.org/
Symposium 30, dated 2002, 250 pp.
Edited by Jon A. Lucy and Anne L. Studholme.
With permission of AFS,
This document has been reproduced for the Internet by
Billfish Tournament Network, Inc.
www.billfishnetwork.com
2336 SE Ocean Blvd. #101
Stuart, Fl 34996
2
ABSTRACT
This study evaluates the performance of circle and comparable size “J” hooks on Atlantic and
Pacific sailfish, Istiophorus platypterus, and to a lesser extent on Pacific blue marlin, Makaira
nigricans. Terminal gear performances were assessed in terms of fishing success, hook location,
and bleeding associated with physical hook damage and trauma. Evaluations of trolling with dead
bait took place off Iztapa, Guatemala, during the spring and summer of 1999, and assessment of
drifting/kite fishing with live bait took place off south Florida during the summer of 1999.
Three hundred and sixty Pacific sailfish were caught in Iztapa, Guatemala, to assess terminal gear
performance: 235 sailfish were on circle hooks and 125 were on “J” hooks. Circle hooks used on
sailfish had hooking percentages (i.e., fish hooked/fish bite) that were 1.83 times higher compared
to “J” hooks. Once the fish were hooked, no difference in catch percentage (i.e., fish caught/fish
hooked) between hook types was detected. Significantly more sailfish were hooked in the corner of
the mouth using circle hooks (85%), as compared with “J” hooks (27%). In contrast, significantly
more sailfish were deep hooked in the throat and stomach with “J” hooks (46%) as compared with
circle hooks (2%). Only one sailfish (1) was foul hooked using circle hooks, while 11 (9%) sailfish
caught on “J” hooks were foul hooked. Sailfish caught on “J” hooks are 21 times more likely to
suffer hook related bleeding than those caught on circle hooks.
Seventy five Atlantic sailfish were caught using circle hooks in the south Florida live bait
recreational fishery to assess possible differences in hook performance between circle hooks with
and without an offset point. No difference in catch percentage or bleeding was found between circle
hooks with no offset, minor offset (about 4 degrees), or severe offset points (about 15 degrees).
However, the percentage of deep hooking in the throat and stomach for circle hooks with a severe
offset (44%) was comparable to the deep hooking percentage for “J” hooks (46%) used in the
Guatemala study. A comparison of circle and “J” hook catch rates of Pacific sailfish and blue
marlin, using logbook catch statistics from recreational fishing off Iztapa, Guatemala, was also
conducted. In general, use of circle hooks resulted in measures of fishing success that were
comparable to or higher than “J” hooks. Circle hooks also minimized deep hooking, foul hooking,
and bleeding. Thus, the use of circle hooks has considerable potential for promoting the live release
of billfish in recreational fisheries.
References in this study to “This Volume” refer to the original publisher American Fisheries Society
Symposium 30,dated 2002 250 pp. edited by Jon. A. Lucy and Anne L. Studholme.
3
INTRODUCTION
Stocks of Atlantic sailfish, Istiophorus platypterus, blue marlin, Makaira nigricans, and white
marlin, Tetrapturus albidus, have been identified as over-exploited or fully-exploited by the
International Commission for the Conservation of Atlantic Tunas (ICCAT) for more than two
decades (ICCAT 1998). The most current summaries of stock status for Atlantic sailfish and marlin
note the historically high rates of fishing mortality observed in recent years (ICCAT 2000). Under
the current harvest rates, the stock status and biomass for these species are expected to continue to
decline. In response to the need to reduce mortality, particularly for the marlins, ICCAT mandated a
25% reduction in landings from 1996 levels, to be implemented by 1999. Given the current
prohibition on retention of billfish in the U.S. commercial longline fishery and the increasingly
restrictive management measures imposed on the U.S. recreational billfish fishery (SAFMC 1988),
alternative approaches for reducing mortality are warranted.
Recent reports indicate that circle hooks used in rod and reel recreational fisheries for striped bass,
Morone saxatilis, chinook salmon, Onchorhynchus tshawytscha, and Atlantic bluefin tuna, Thunnus
thynnus, have been shown to reduce deep hooking significantly and thus promote the live release of
these species (Grover et al. This Volume; Lukacovic and Uphoff Jr., This Volume; Skomal et al.
This Volume). Circle hooks have been used for many years in both commercial pelagic and
demersal longline fisheries, but rod and reel recreational fisheries for sailfish and marlin have not
traditionally used circle hooks as the primary terminal gear. Although nonconsumptive fishing
practices (i.e., catch and release fishing) among U.S. recreational billfishermen in the Atlantic
started in the late 1960s and has increased dramatically in recent years to about 90% release (Farber
et al. 1997), it was only recently that advances in circle hook rigging techniques using natural bait
allowed increased use of circle hooks for trolling/pitch baiting or live bait drifting for sailfish and
marlin1, 2. This study was initiated in response to requests for more information on the use of circle
hooks for catching billfish in order to promote the live release of these important resources
(USDOC 1999). Specific objectives were: (1) to compare hooking and catch percentages between
terminal gear (circle and “J” hooks) used in the trolling/pitch bait recreational fisheries for billfish;
(2) to assess the hook location and degree of hook associated physical damage and bleeding
between terminal gears; and (3) to evaluate the different levels of offset points in circle hooks
relative to catch percentages, hook location, and bleeding in the live bait recreational fishery for
sailfish.
4
MATERIALS
Terminal Gear Comparisons Using Dead Natural Bait
We defined circle hooks as hooks having a point that is perpendicular to the main hook shaft,
whereas “J” hooks are defined as hooks having a point parallel to the main hook shaft (Figure 1).
Iztapa, Guatemala, was chosen as the primary research site because of high seasonal catch rates for
sailfish and local cooperation of the fishing fleet, insuring that sufficiently high sample size targets
could be obtained in a minimum amount of time for a species that is commonly known as a rare
event species (Prince and Brown 1991). The fishing fleet in Iztapa, Guatemala consisted of five
modern recreational vessels 30–40 ft in length, all of which participated in the study, the F/V
Captain Hook, F/V Magic, F/V Intensity, F/V Pelagian, and the F/V Classic.
In order to promote valid comparisons of terminal gears, both hook types were rigged in the same
manner on the forehead of ballyhoo, Hemirammphus brasiliensis (Figure 1). Ballyhoo are the bait
of choice for trolling/pitch baiting Pacific sailfish off Iztapa, Guatemala, and were used in this
study. Our choice of hooks were the Mustad2, 3 short shank “J” hook (size 6/0, model 9175) and the
Eagle Claw2, 3 circle hook (size 7/0, model L2004), which has a minor offset point of less than 4
degrees. An offset is a deviation of the hook point relative to the main axis of the hook shaft. The
Mustad “J” hook has no offset point and a silver finish, while the circle hook has a pearl gray finish.
The difference in hook color between hook types helped facilitate identification of hooks embedded
in live sailfish at boatside, where hook location and hook related damage assessment was
conducted. Circle hook styles and sizes are not consistent between models, nor do they correspond
to hook size for traditional “J” hooks1, 2. Although the commercially listed size of the two hooks
used in this study were different (“J” hook was 6/0 and circle hook was 7/0), the actual size of the
hook types was almost identical (Figure 1). Traditional hook setting techniques of jerking the
fishing rod vertically were used for sailfish caught on “J” hooks. These techniques were modified
for circle hooks1, 2 to a more passive approach, by simply reeling the line tight as the fish swam
away from the vessel.
Catch/Hooking Performance and Hooking Injury
A fish bite was considered to be a strike that resulted in the line being pulled out of the outrigger pin
while trolling, or a bite witnessed visually during pitch bait fishing. Visual confirmations of species
identification were made to ensure sailfish catch and hooking percentages were only for sailfish.
Hooking percentage was defined as the number of fish hooked divided by the number of fish bites.
A fish was considered hooked when it took drag and continued to remain on the line for at least 10
s. Catch percentage was defined as the number of sailfish brought close enough to boatside for the
crew to touch the leader (i.e., a catch), divided by the number of sailfish hooked.
Fish injuries associated with hooking were characterized by evaluating hook location, as well as
incidence and amount of bleeding. When possible, fish were pulled out of the water by the crew
using the upper bill and the head of the fish was lifted onto the gunnel of the vessel, the mouth
opened, and the hook location and amount and source of bleeding were noted (Figures 2, 3, 4, and
5).
______________________________________________________________________________________
1Fogt, J. 1999. Circle of Life. Marlin Magazine. Vol. 18(3): 44-50.
2Rizzuto, J. 1998. Get to the point. Marlin Magazine. Vol. 17(3): 46-50.
3The mention of commercial products or entities does not imply endorsement by the National Marine Fisheries Service
or the authors.
5
FIGURE 1
Figure 1. Terminal gears rigged on ballyhoo, Hemirammphus brasiliensis, used in the troll/pitch bait
recreational fishery for billfish in Iztapa, Guatemala. Top, long shank “J” hook (Mustad model 3407, size 8/0)
used prior to 1998; middle, short shank “J” hook (Mustad model 9175, size 6/0); and bottom, circle hook
(Eagle Claw model L2004, size 7/0) used in this study.
Since the recreational fishery of Iztapa, Guatemala is almost exclusively catch and release, more
detailed evaluations of hook damage using autopsy examinations of dead fish were not made. If
hook location or amount and location of bleeding were unclear prior to release, these data were not
recorded. Hook location categories included: (1) corner of mouth or jaw hinge (Figure 2); (2) lower
or upper jaw; (3) deep hooked, including hooks lodged inside the mouth, throat or deeper, the
upper/lower palate, pharynx, esophagus, gill arch, or stomach, (Figures 3 and 5); and (4) foul
hooked (i.e., hooks lodged outside of the mouth, Figure 4). Some typical foul hooked locations
included the upper bill, operculum, dorsal musculature, and eyeball.
The amount of bleeding was subjectively categorized into three general levels based on the volume
of blood observed: (1) severe bleeding; (2) moderate bleeding; and (3) minor bleeding. The general
location of bleeding was noted whenever possible, but data on source of bleeding could not be taken
consistently because not every fish could be examined out of the water.
6
FIGURE 2
Figure 2. Eighty five percent of sailfish caught on circle hooks had them lodged in the hinge of
the jaw. Arrow indicates hook location.
FIGURE 3
Figure 3. Forty six percent of sailfish caught on “J” hooks had them lodged inside the mouth,
throat, gill arch, esophagus, pharynx, or stomach(i.e., deep hooked). Arrow indicates hook
location.
7
FIGURE 4
Figure 4. Nine percent of sailfish caught on “J” hooks were foul hooked, such as this hook
which lodged on the outside of the upper bill. See text for definition of foul hooking.
FIGURE 5
Figure 5. Upper palate wounds incurred by sailfish were exclusively “J” hook related injuries.
The depth and location of this upper palate laceration (lower arrow) also resulted in
hemorrhaging in the eye (upper arrow).
8
Gear Specific Fishing Success in Guatemala
A comparison of catch rates reported by the Iztapa recreational fleet was conducted to evaluate the
fishing success for Pacific sailfish and blue marlin. Captains in the fleet have kept detailed logbook
records of the number of fish bites and fish caught since 1993. The analysis used the catch data
information from the fishing year June 1996 through June 1997, when the fleet used “J” hooks
exclusively and from the fishing year June 1998 through June 1999, when the fleet had switched
entirely to circle hooks. Because there was no overlap in periods between the use of the two hook
types in time, it was not possible to distinguish catch rate effects due to the fishing gear used and
changes in stock abundance between years. This limitation would apply to any statistical analysis
using these data. Thus, we assumed that the stocks were equally available in number and spatiotemporal
distribution between the two consecutive years. Standardized catch rates were computed
using a generalized linear mixed model (GLMM), which discriminated between effects on catch
rates due to seasonality, boat-captain characteristics, and hook type. Catch rates were defined as the
number of fish caught per day (CPUE).
Evaluation of Circle Hooks in the South Florida Sailfish Live Bait Fishery
Three types of Eagle Claw circle hooks, with different degrees of an offset point, were used to
assess hook performance in the live bait fishery for sailfish off south Florida. Eagle Claw3 model
197 L has an offset point of 15 degrees (severe), model L2004 has an offset point of about 4 degrees
(minor), and model L2004 EL has no offset point (all hooks were size 7/0). These differences
allowed us to compare catch percentages and potential hook damage among circle hooks with
different degrees of offset. Two live bait fishing techniques were involved: (1) drifting with flat
lines with and without weights; and (2) live bait fishing with kites. The primary live baits of choice
were Atlantic thread herring (Opisthonema oglinum), blue runner (Caranx crysos), and bigeye scad
(Selar crumenopthalmus). Occasionally smaller baits were used, including round scad (Decapterus
punctatus) and scaled herring (pilchards, Harengula jaguana). Three south Florida charter boat
captains who specialize in live bait fishing for sailfish participated in this study during the summer
of 1999.
Statistical Analyses
The Chi-Square goodness of fit procedure (Steel and Torrie 1960) was used to examine the null
hypothesis that there were no differences in catch percentages, hooking percentages, hook location,
or associated bleeding between terminal gears in the sailfish fishery off Guatemala. In cases where
the number of observations per cell was lower than the number of degrees of freedom, Fisher’s
exact test or Odds ratio test was used instead (Shoukri and Pause 1999). For comparisons of data
with more than 2 levels per factor, a Cochran-Mantel-Haenszel (CMH) test was used. This test
evaluates the association between X and Y (row levels) in any of the strata (Shoukri and Pause
1999)). Chi-square and CMH tests evaluated whether or not there is independence between two
factors. If the null hypothesis was rejected (i.e., nonindependence between factors), a
correspondence analysis test was carried out to show the degree of association among levels based
on a weighted principal components evaluation (Manly 1994). Similar procedures were also used to
evaluate differences associated with the degree of offset in circle hooks used in the live bait fishery
for sailfish off south Florida. Catch rates (CPUE) for blue marlin and sailfish based on captains’
logbooks of the recreational fishing fleet in Guatemala were evaluated for differences associated
with hook type by using a Generalized Linear Mixed model (GLMM) approach (SAS 1997).
9
RESULTS
Terminal Gear Comparisons Using Dead Natural Bait
From March through May, 1999, a total of 590 sailfish bites was recorded off Iztapa, Guatemala
(Table 1). Of these, 461 sailfish were hooked and 360 were caught, examined at boatside and
released. The number of sailfish hooked and caught on each terminal gear are as follows: 300 were
hooked on circle hooks and 235 of these were caught, while 161 were hooked on “J” hooks and 125
of these were caught (Table 1). Circle hooks showed significantly higher (p < 0.002) hooking
percentages compared to “J” hooks (Table 2). Odds ratio tests indicated that on average, circle
hooks were 1.83 times more likely to hook a sailfish than a “J” hook (Table 2). In contrast, once a
fish was hooked, the catch percentage (78%) was virtually identical for each type of terminal gear).
Chi-square and CMH tests indicated that the percentage of hook location also differed significantly
(p < 0.001) between circle and “J” hooks (Table 2). The correspondence analysis was then used to
determine particular associations between hook type and hook location levels. This test showed that
circle hooks were closely associated with hooking in the corner of the mouth, while “J” hooks were
closely associated with deep hooking and foul hooking (Table 2; Figure 6).
Seventy-one of the 125 sailfish caught on “J” hooks were observed bleeding, as compared to 14 of
235 sailfish caught on circle hooks (Table 1). This difference was highly significant (p £ 0.001), and
the Odds Ratio test indicated that a sailfish caught on a “J” hook was 20.75 times more likely to
bleed compared to one caught on a circle hook (Table 2). Analysis of the degree of bleeding
associated with the two types of terminal gear indicated a significant difference (p < 0.001, Table
2). Correspondence analysis showed that “J” hooks were highly associated with
minor/moderate/severe bleeding, while circle hooks were associated with no bleeding (Figure 7,
Tables 1 and 2).
TABLE 1
“J” Hooks Circle Hooks a
number % number %
fishing success
bites 225 365
fish hooked 161 72 300 82
fish caught 125 78 235 78
hook location
hooked in corner of mouth 34 27 200 85
hooked in lower or upper jaw 21 17 30 13
deep hooked 58 46 4 2
foul hooked 11 1 0.4
unknown hook location 1 1 0 0
bleeding
severe bleeding 32 26% 6 3%
moderate bleeding 23 18% 4 2%
minor bleeding 16 13% 4 2%
no bleeding 54 43% 221 94%
bleeding source
gills 13 3
gut 8 1
eyes 1 0
a offset 4o
Table 1. Circle and “J” hook comparisons for Pacific sailfish caught in the recreational dead bait
fishery off Iztapa, Guatemala, from March through May, 1999. See text for descriptions of terminal
gear and definitions of catch and hooking percentages, hook locations, and degree of bleeding.
10
TABLE 2
Comparison
Circle
hook
“J”
hook
Test
Statistic
value
p
Odds ratio
95%
confidence
bounds
Hook percentage = fish
hook/ number of fish bites
82%
(300/365)
72%
(161/225)
Chi-square
9.217
0.002
Circle /
J hook
1.831
1.236
2.723
Catch percentage = fish
caught / number fish hooked
78%
(235/300)
78%
(125/161)
Chi-square
0.029
0.864
Circle /
J hook
1.041
0.656
1.652
Hook location
Corner of mouth
200
34
155.235
0.001
N/A
Deep
4
58
Chi-square
Contingency
table
Foul
1
11
39.318
0.001
N/A
Upper/lower Jaw
30
21
Cochron-Mantel-
Haenszel Nonzero
correlation
Bleeding (Yes/No)
14 / 235
71 / 125
Chi-square
116.945
0.001
J hook
/ Circle
20.755
10.89
39.59
Degree of bleeding
Severe
6
32
116.582
0.001
N/A
Moderate
4
23
Chi-square
Contingency
table
Minor
4
16
5.127
0.024
N/A
None
220
54
Cochran-Mantel-
Haenszel Nonzero
correlation
Table 2. Statistical comparison of circle hook and AJ@ hook caught sailfish from the recreational fishery off Iztapa,
Guatemala, March through May, 1999. See text for descriptions of terminal gear and definitions of hook/catch percentage,
hook location, bleeding, and degree of bleeding.
11
FIGURE 6
Figure 6. Distribution of hook location by hook type from Pacific sailfish caught off Iztapa, Guatemala (A, bar
width is proportional to sample size). Hook locations were characterized as corner of mouth, upper/lower jaw,
deep, and foul hooked. See text for definitions of hook locations. Correspondence analysis plot (B).
12
FIGURE 7
Figure 7. Distribution of degree of bleeding by hook type (circle and “J” hooks) for Pacific sailfish (A, bar
width is proportional to sample size). Bleeding was characterized as none, minor, moderate, or severe. See
text for definitions of bleeding categories. Correspondence analysis plot (B).
13
Gear -Specific Fishing Success in Guatemala
Catch data derived from captain’s logbooks included species, number of fish caught, bites, and
number of fish raised, number of fishing days per month, and vessel name from 1996 through
1999 (Table 3; Figure 8). Sample sizes for sailfish and blue marlin during both fishing years
(1996/97 sailfish n = 5,778, blue marlin n = 60; 1998/99 sailfish n = 6,639, blue marlin n = 46)
were high (Table 3).
TABLE 3
“J” Hooks(1996/97) Circle Hooks(1998/99)
Sailfish
(n)
Blue marlin
(n)
Sailfish
(n)
Blue marlin
(n)
Fishing days 776 776 517 517
Billfish raises 13,344 134 15,198 102
Billfish bites 10,297 106
11,10 85
Billfish caught 5,778 60 6,639 46
Catch percentage a (%) 56 57 57 54
Nominal CPUE (std mean)b 7.443
(0.489)
0.2011
(0.0669)
12.015
(0.884)
0.2617
(0.0533)
a Catch % = number caught/number bites
b CPUE = number caught/number fishing days per month.
Table 3. Summary of catch statistics for Pacific sailfish and blue marlin from captains= logbooks of the
recreational fishing fleet in Iztapa, Guatemala, by hook type and species. “J” hooks were used during the fishing
year, June, 1996-June, 1997, and circle hooks were used during the fishing year June, 1998-June, 1999.
FIGURE 8
Figure 8. Nominal (diamonds) and estimated (horizontal line) catch per unit of effort (CPUE) based on
logbook data for Pacific sailfish and blue marlin by quarter (1,2,3 and 4), hook type (Circle and J-type
hooks), and boat from the recreational fleet off Iztapa, Guatemala.
14
As mentioned earlier, if we assumed that availability and stock density was similar between the
1996/7 and 1998/99 fishing years, differences in catch rates could be attributed to the terminal gear
used. Thus, analysis of catch rates (catch per unit effort [CPUE] = number of fish/fishing day) were
performed for sailfish and blue marlin using a GLMM model assuming a lognormal error
distribution with autoregressive covariance structure (Littell et al. 1996). This covariance model
accounts for large correlations for nearby time observations within each boat compared to distant
observations. The factors included in the GLMM were quarter grouping of monthly CPUE’s, hook
type (“J” hook and circle hook) and boat. The boat effect was considered a random factor. First
level interactions of main factors were also evaluated. The CPUE model can be expressed as:
where Xi is the vector of fixed factors of hook type, and quarter, di,j is the random block factor
boat, and e is the normally distributed error. The mean CPUE for each hook type was estimated
from the least square means (LSMeans), and this variable was used as a test for significance
between hook types. The Akaike’s Information Criterion (AIC) and Schwarz’s Bayesian
Criterion (SBC) showed that the autoregressive covariance model explained the overall
variability (Table 4) better than the compound symmetric and unstructured covariance models
(Littell et al. 1996). For sailfish, the model results showed that the hook type factor was
significant, and the mean estimated CPUEs were 10.25 sailfish/fishing day for circle hooks and
6.34 sailfish/fishing day for “J” hooks (Table 4; Figure 9). In contrast, for blue marlin, model
results showed that hook type was not a significant factor, and mean estimated CPUEs were
0.174 blue marlin/fishing day and 0.167 blue marlin/fishing day for circle hooks and “J” hooks
respectively (Table 4; Figure 9). Only in the case of blue marlin, the quarter was a significant
factor, reflecting the seasonal character of the blue marlin fishery off Iztapa, Guatemala.Use of
Circle Hooks in the South Florida Sailfish Live Bait Fishery
Seventy-five sailfish were caught on circle hooks using live bait in the recreational fishery off South
Florida (Table 5). Analysis of catch percentages (fish caught/fish bites) using the CMH test showed
no differences associated with the three categories of offset circle hooks (Table 6). Similar results
were obtained using Fisher’s exact test if the samples from minor offset and no offset were
combined and compared to the severe offset category. However, the analysis of hook location
indicated that the level of circle hook offset and hook location were not independent (Table 6).
Correspondence analysis revealed that severe offset circle hooks were highly associated with deep
hooking, while minor and no offset circle hooks were associated with jaw and corner of mouth hook
locations (Table 6; Figure 10). Bleeding was analyzed by grouping minor and no offset observations
and this category was compared to severe offset circle hooks using the Fisher’s exact test. Results
indicated no statistically significant differences in bleeding between the offset categories (Table 6).
15
TABLE 4
Sailfish
Blue marlin
Covariance structure models
Description
Unstructured
matrix
compound
symmetric
Autoregressive
(1)
Unstructured
matrix
Autoregressive
(1)
Observations
88
88
88
53
53
Residual log likelihood
-74.376
-76.778
-76.954
-61.689
-60.278
Akaike=s Information criterion
-76.376
-78.778
-78.954
-63.867
-62.278
Schwarz=s Bayesian criterion
-78.795
-81.197
-81.373
-65.738
-64.150
Model Summary
Class
Level
Values
Hook type
2
Circle
J-type
Quarter
4
Jan-Mar
Apr-Jun
Jul-Sep
Oct-Dec
Boat
5
CaptHook
Classic
Intensity
Magic
Pelagian
Blue marlin Test for fixed Effects
Source
NDF
DDF
Type III F
p > F
Hook type
1
44
0.04
0.834
Quarter
3
44
11.17
0.0001
Least Square Means
Difference of L S Means for Hook type
Hook type
LSMean
Std error
df
Difference
Std err Diff
t
p > |t|
Circle
-1.7573
0.1375
44
0.0384
0.18202
0.210
0.8339
J-Type
-1.7957
0.1328
44
Sailfish Test for fixed Effects
Source
NDF
DDF
Type III F
p > F
Hook type
1
79
10.85
0.0015
Quarter
3
79
0.72
0.5403
Least Square Means
Difference of LSMeans for Hook type
Hook type
LSMean
Std error
df
Difference
Std err Diff
t
p > |t|
Circle
2.3210
0.1122
79
0.4797
0.1456
3.29
0.015
J-Type
1.8413
0.1102
79
Table 4. Generalized linear mixed model (GLMM) analyses for Pacific sailfish and blue marlin catch rates from
logbook reports of the recreational fisheries off Iztapa, Guatemala for two separate fishing years, June 1996/June
1997 and June 1998/June1999.
16
FIGURE 9
Figure 9. Estimated mean (LSMean) CPUE by hook type and 95% confidence intervals for Pacific sailfish (A)
and blue marlin (B) based on logbook data from the recreational fleet off Iztapa, Guatemala. Long shank “J”
hooks were used during the fishing year 1996/97 and circle hooks were used during the fishing year 1998/99.
17
TABLE 5
Offset Circle Hooks
Severe a
(L197)
Minor b
(L2004)
None c
(L2004 EL)
Minor & None
combined
number
%
number
%
number
%
number
%
Fishing Success
Fish hooked
18
22
47
69
Fish caught
16
89
18
82
41
87
59
86
Hook location
Corner
2
11
7
32
12
26
19
28
Jaw
3
17
4
18
7
15
11
16
Deep
8
44
3
14
3
6
6
9
Foul
0
0
0
0
0
0
0
0
Unknown
3
17
4
18
19
40
23
34
Bleeding
Severe
1
0
0
0
Moderate
0
0
2
2
Minor
0
0
1
1
None
15
18
38
56
a Eagle Claw model number L197 with 15o offset
b Eagle Claw model number L2004 with 4o offset
c Eagle Claw model number L2004EL
Table 5. Atlantic sailfish caught using live bait and circle hooks with different offset points off south Florida. Severe
and minor offset hooks had 15o and 4o offsets, respectively. See text for definition of offset point, catch percentage,
hook location, and degree of bleeding. The model of Eagle Claw circle hooks used in this study is given in
parentheses.
TABLE 6
Table 6. Atlantic sailfish caught on circle hooks with three different offset points in the live bait recreational fishery off
south Florida. Samples for no offset and minor offset were combined into a single category for the analysis of bleeding.
Comparison No offset Minor offset Severe offset Test statistic
value
p Odds ratio 95% confidence
bounds
Catch percentage =
fish caught/ fish bites 87% 82% 89% Chi-square
Contingency table
0.507 0.776 N/A
(41/47) (18/22) (16/18) Cochran-Mantel-
Haenszel 0.501 0.778 N/A
Hook location
Corner of mouth 12 7 2 17.205 0.009
Deep 3 3 8
Chi-square
Contingency table
Upper/lower Jaw 7 4 3 Likelihood Ratio
Chi-square 15.859 0.015
Unknown 19 4 3 Fisher's Exact test 0.014
Bleeding
Yes/No
3/ 59 1/15 Fisher's Exact test 0.626 Severe
/Minor 0.804 0.077 8.387
18
FIGURE 10
Figure 10. Distribution of hook location by degree of offset in circle hooks from Atlantic sailfish caught
off South Florida (A, bar width is proportional to sample size), and correspondence analysis plot (B).
19
DISCUSSION
Fishing Success
One of the first concerns in attempting to change the terminal gear in any recreational fishery is that
such a change will negatively impact fishing success1, 2, 4. This study showed that catch percentages
were unaffected by a change in hook type using the different terminal gears during dead bait
trolling/pitch baiting for sailfish in Iztapa, Guatemala. Catch percentages for sailfish and blue
marlin obtained from captain’s logbooks in previous years were also consistent with these results.
Analysis of standardized catch rates from captain’s logbooks indicated that for Pacific sailfish, the
number of fish caught per fishing day was higher during 1998–1999 year when the fleet used circle
hooks. However, this analysis could not differentiate between increases in fish availability and hook
type catchability. Sailfish catch percentages were also high for circle hooks fished with live bait off
Florida. However, it should be noted that catch percentages and catch rates for circle hooks
depended on the novel forehead hook placement used to rig the baits, as well as a certain amount of
training to implement a more passive approach to setting circle hooks. Our findings on fishing
success were similar to those reported by Skomal et al. (This Volume), who found no statistical
differences in recreational catch rates between circle hooks and “J” hooks in the dead chunk bait
fishery for juvenile Atlantic bluefin tuna.
Circle hooks fished in the manner described in this study were found to have a higher hooking
percentage for sailfish compared with “J” hooks and this result was corroborated with field
observations. For example, it was observed that “J” hooks often de-hooked during the fight when
sailfish jumped out of water and this was less likely to occur with a circle hook. The curved point of
the circle hook appeared to reduce de-hooking under these circumstances. Recreational anglers have
noticed similar advantages of using circle hooks while targeting tarpon (Megalops atlanticus) in
South Florida. In many Florida locations, circle hooks are now the terminal gear of choice for
tarpon fishers because of their ability to hold in place, despite the fact that this species is known for
dramatic leaps out of the water4. Skomal et al. (This Volume) reported that once Atlantic bluefin
tuna were hooked, there were three times as many instances of de-hooking using “J” hooks as
compared with circle hooks. Overall, catch percentages (sailfish, blue marlin), hooking percentages
(sailfish), and catch rates (sailfish) reported in this study generally comparable with or were higher
for circle hooks than for “J” hooks. These results are likely to encourage recreational billfishing
constituents, who might not otherwise be receptive to changes in their fishing tackle, to consider the
use of circle hooks as a terminal gear alternative to “J” hooks.
Physical Injuries Due to Hooking
It was beyond the scope of this study to measure release mortality directly, due in part to the
difficulty of holding billfish in captivity (Post et al. 1997; de Sylva et al. 2000) and the
prohibitively high cost of using popup satellite tags to monitor postrelease survival (Graves et al.
This Volume). However, hook location, physical hooking injuries, and amount of bleeding
between hook types were evaluated in this study and these data provide insight into survival
potential. Hooks found in the jaw hinge or mouth, or fish bleeding from these locations, were not
considered life threatening. Conversely, hooks found in the upper palate, throat, pharynx,
esophagus, or in the stomach and fish showing lacerations or bleeding from these areas were
considered potentially lethal. The of lack autopsies to examine hook related injuries closely
________________________________________________________
4Jordan, J. 1999. Going full circle. Big Game fishing Journal. Offshore Informational Publications, Inc. Point
Pleasant, N.Y. Vol. 12(3): 52-62.
20
prevented estimates of potential release mortality in this study. Skomal et al. (This Volume) were
able to conduct detailed autopsies on Atlantic bluefin tuna in their hook damage study and produced
estimates of 2% potential release mortality for bluefin tuna caught on circle hooks and 28%
potential mortality for tuna caught on “J” hooks. Nevertheless, difficulties in holding tuna and
billfish in captivity or making direct in situ measurements continue to hinder release mortality
studies of many species.
The results of this study clearly indicate that the use of circle hooks can minimize deep hooking and
foul hooking in the recreational trolling/pitch bait fisheries for sailfish. Numerous other studies have
found similar results for a wide variety of species, including striped bass (Lukacovic and Uphoff
This Volume), Atlantic bluefin tuna (Skomal et al. This Volume), and chinook salmon (Grover et al.
This Volume).
Although deep hooking was considered to be potentially lethal, sailfish and marlin are very large
species that may not necessarily die if deep hooked in the throat, pharynx, esophagus. or stomach.
For example, on numerous occasions, rusty hooks have been found in the stomachs of large billfish
that appeared to be healthy otherwise (E. Prince, unpublished observation). In addition, it is
common for all billfish to evert their stomachs outside their mouth once hooked (Harvey 1989,
Figure 3). This appears to be a protective mechanism used by billfishes to dislodge bones and other
indigestible materials that they routinely consume (Rivas 1975; ICCAT 1999). Therefore, having a
bone or hook penetrate the stomach of a billfish may not necessarily result in mortality unless it also
injured a vital organ and/or initiated a lethal infection.
Only one sailfish mortality was documented during this study. This individual was caught on a “J”
hook, which appeared to have cut one of the major gill arches. The assumption was that this fish
bled to death. Conversely, some of the injuries that were not associated with deep hooking could
also be potentially lethal. For example, several instances were documented where “J” hooks were
foul hooked in the eye. If eye injuries result in blindness, then this injury could potentially affect
survival because Istiophorids are highly dependent on daytime sight feeding in the upper portions of
the water column (Rivas 1975; Block at al. 1992). Blindness in one eye would negatively impact
peripheral vision and could seriously inhibit the ability of these species to feed. Numerous instances
were also documented where “J” hook injuries that were not foul hooked could have caused eye
damage. For example, in some cases “J” hooks caused deep lacerations to the upper palate (Figure
5) which, on occasion, affected the occipital orbit and resulted in hemorrhaging in the eye. These
types of injuries can be deceptive and are particularly difficult to observe in fish at boatside
because, in most cases, the lack of tissue in the upper palate results in the hook de-hooking from its
initial location and re-hooking in another area. Although these fish would appear lively alongside
the boat, upper palate injuries could be potentially lethal due to eye damage. Upper palate injuries
can also affect the integrity of the cranial cavity by making this area susceptible to infection. Belle
(1997) reported that numerous juvenile Atlantic bluefin tuna caught on trolled cider plugs with “J”
hooks suffered upper palate injuries. However, these injuries were not immediately evident upon
capture and were only detected after conducting autopsies on mortalities observed in the tuna held
in a sea pen for up to two weeks. Belle (1997) hypothesized that upper palate injuries suffered
during capture resulted in cranium related infections and these infections likely caused delayed
mortality in bluefin tuna.
Perhaps the most significant finding in this study was the evaluation of bleeding, which indicated
that sailfish caught on “J” hooks were 20 times more likely to bleed compared with those caught on
circle hooks. This result was supported by correspondence analysis of the degree of bleeding in
which sailfish caught on “J” hooks were associated with severe, moderate or minor bleeding while
21
sailfish caught on circle hooks were associated with no bleeding. The reduced bleeding of circle
hook caught sailfish has been cited as the primary reason why recreational anglers are voluntarily
promoting the use of circle hooks over “J” hooks for dead bait trolling/pitch bait fishing for these
species1, 2, 4.
Although small sample sizes for the main treatments in the live bait study precluded more rigorous
statistical analysis of fishing success, hook location, and amount of bleeding (Table 5), several
trends in these data are noteworthy. For example, the severe offset deep hooking percentage (44%)
was two to three times higher than minor or no offset deep hooking percentages. This result was a
bit surprising because prior to this finding, we had consistently experienced much lower overall
deep hooking percentages (<10%) using circle hooks. Lukacovic and Uphoff (This Volume) also
found a high deep hooking percentage (46%)on striped bass using the same model severe offset
circle hook as used in this study. Malcoff (Personal communication5) examined the use of circle
hooks on summer flounder, Paralichthys dentatus, and found that the severe offset in the circle
hook used resulted in higher deep hooking percentages than expected. The association of severe
offset circle hooks and high rates of deep hooking has management implications because any
benefits of minimizing deep hooking rates realized when using circle hooks can be circumvented by
bending the circle hooks with pliers to increase the degree of offset.
22
CONCLUSIONS
The current high rate of fishing mortality and depressed stock status of most Atlantic Istiophoridae
justify development of alternative approaches for reducing hook induced mortality for these species.
One such approach would be the modification of terminal gear in order to reduce hook related
injuries and trauma experienced during catch and release fishing (Muoneke and Childress 1994).
This study compared circle hook and similar sized “J” hook performance while trolling/pitching
dead bait or drifting live bait for billfish; methods commonly used by anglers targeting these
species. Rates of fishing success and hooking percentage were comparable or higher for circle
hooks compared to “J” hooks. In addition, use of circle hooks resulted in lower rates of deep
hooking, foul hooking, and bleeding compared to “J” hooks. During live bait experiments, severe
offset circle hooks were associated with increased deep hooking percentages that were similar to
percentages observed for “J” hooks using dead bait (46%). Given the multiple benefits of
minimized hook related injury along with comparable or improved fishing success and hooking
percentages using circle hooks in dead or live bait recreational fisheries for billfish, this terminal
gear appears to have potential as a means to promote the live release of these species.
23
ACKNOWLEDGMENTS
The investigators would like to thank the captains, crews, and fisherman from Fins and Feathers
fleet (including vessels F/V Captain Hook, F/V Magic, F/V Intensity, F/V Pelagian and F/V
Classic) in Iztapa, Guatemala, for their cooperation and enthusiastic support in providing their
logbooks, experience and boats to carry out this study. In particular, we thank Captain Ron Hamlin
of F/V Captain Hook for his innovative bait rigging and initial use of circle hooks in the sailfish
fishery off Guatemala. The authors are grateful to south Florida Captains Nick Smith, Angelo
Durante and Bouncer Smith, for their willingness to participate in the live bait portion of the study.
This research was partially funded by a grant from Tim Choate of ARTMARINA in Miami, Florida,
and owner of the Fins and Feathers Resort in Iztapa, Guatemala. Without Choate’s active
participation and enthusiasm, this project would not have been possible. Circle hooks used in this
study were provided by George Large and Mike Praznovsky of Eagle Claw Fishing Tackle, Wright
& McGill Company.
24
REFERENCES
Belle, S. 1997. Bluefin tuna project. Final Report for National Oceanic and Atmospheric
Administration Award NA37FL0285. New England Aquarium, Edgerton Research Laboratory,
Central Wharf, Boston, Massachusetts 62 pp.
Block, B. A., D. T. Booth, and F. G. Carey. 1992. Depth and temperature of the blue marlin,
Makaira nigricans, observed by acoustic telemetry. Marine Biology 114:175–183.
de Sylva, D. P., W. J. Richards, T. R. Capo, and J. E. Serafy. 2000. Potential effects of human
activities on billfishes (Istiophoridae, and Xiphiidae) in the western Atlantic ocean. Bulletin of
Marine Science., 66: 187-. 198.
Farber, M. I., and eight coauthors. 1997. 1994/1995 Report of the Southeast Fisheries Science
Center Billfish Program. National Oceanic and Atmospheric Administration Technical
Memorandum NMFS-SEFSC-398.
Graves, J. E., B. E. Luckhurst, and E. D. Prince. This Volume. An evaluation of pop-up satellite tag
technology to estimate post-release survival of Atlantic blue marlin (Makaira nigricans). §abstract.
In Catch, and Release Symposium in Marine Recreational Fisheries.
Grover, A. M., M. S. Mohr, and M. L. Palmer-Zwahlen. This Volume. Hook, and release mortality
of chinook salmon from drift mooching with circle hooks: management implications for
California’s ocean sport fishery. In Catch, and Release Symposium in Marine Recreational
Fisheries.
Harvey, G. C. 1989. An historical review of recreational and artisanal fisheries for billfish in
Jamaica, 1976-1988. Collect. volume Sci. Pap. International Commission for the Conservation of
Atlantic Tunas (ICCAT), Madrid, Spain 30(2) 440-450.
ICCAT. 1998. Report for biennial period, 1997-98. ICCAT, Spain. Part 1 (1997), Vol 2.
ICCAT. 1999. Executive Summary Report for Blue Marlin (1999). Report for biennial period,
1998-99. ICCAT, Madrid, Spain. Part 1 (1998), volume 2.
ICCAT. 2000. Report of the standing committee on research, and statistics (SCRS). ICCAT,
Madrid, Spain.
Littell, R. C., G. A. Milliken, W. W. Stroup, and R. D. Wolfinger. 1996. SAS Systems for Mixed
Model. SAS Institute, Cary, North Carolina, 633 pp.
Lukacovic, R., and J. H. Uphoff, Jr. This Volume. Hook location, fish size, and season as factors
influencing catch, and release mortality of striped bass caught with bait in Chesapeake Bay.
Extended §abstract. In Catch, and Release Symposium in Marine Recreational Fisheries.
Manly, Brian F. J. 1994. Multivariate Statistical Methods. A primer 2nd edition. Chapman and Hall,
CRC.
25
Muoneke, M. I., and W. M. Childress. 1994. Hooking mortality: a review for recreational fisheries.
Review Fishery Science. 2:123–156.
Post, J. T., J. E. Serafy, J. S. Ault, T. R. Capo, and D. P. de Sylva. 1997. Field and laboratory
observations on larval Atlantic sailfish (Istiophorus platypterus) and swordfish (Xiphias gladius).
Bulletin of Marine Science, 60:1026–1034.
Prince, E. D., B. B. Brown. 1991. Coordination of the ICCAT enhanced research program for
billfish. American Fisheries Society Symposium 12:13–18, 1991.
Rivas, L. R. 1975. Synopsis of biological data on blue marlin, Makaira nigricans, Lacepede, 1802.
In R. S. Shomura and F. Williams, editors. Proceedings of the International Billfish Symposium
Kailua-Kona, Hawaii, 9-12 August 1972. Part 3. Species Synopses. National Oceanic and
Atmospheric Administration Technical Report NMFS SSRF-675.
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environmental impact statement, regulatory impact review, and initial regulatory flexibility analysis
for the Atlantic billfishes.
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SAS Institute Inc., Cary, North Carolina.
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Press LLC. 384 pp.
Skomal, G. B., B. C. Chase, and E. D. Prince. This Volume. A comparison of circle hook, and
straight hook performance in recreational fisheries for juvenile Atlantic bluefin tuna. In Catch, and
Release Symposium in Marine Recreational Fisheries.
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Company, Inc. New York.
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26
FOOTNOTES
1 Fogt, J. 1999. Circle of Life. Marlin Magazine. Vol 18(3): 44–50.
2 Rizzuto, J. 1998. Get to the point. Marlin Magazine. Vol. 17(3): 46–50.
3 The mention of commercial products or entities does not imply endorsement by the National
Marine Fisheries Service or the authors.
4 Jordan, J. 1999. Going full circle. Big Game fishing Journal. Offshore Informational Publications,
Inc. Point Pleasant, N.Y. Vol. 12(3): 52–62.
5 Malcoff, M. Personal communication.
Circle Hook Research
Numerous published studies conclude that using circle hooks instead of traditionally shaped "J" hooks can significantly reduce the number of fish killed by anglers practicing catch and release fishing. In a review of 43 circle hook studies, Cook and Suski (2004) founds that in general, hooking mortality rates for fish released from circle hooks were approximately half of those for fish released from "J" hooks. A recent study by Horodysky & Graves (200S) has shown that by using circle boob instead of "J" -hooks, recreational anglers can reduce the mortality of released white martin by two-thirds or more. Circle hooks tend to catch in the jaw or comer of a fish's mouth instead of in its gut or throat. Prince et aI. (2002) found J-hooks more than 20 times more likely to cause bleeding in sailfish, relative to circle hooks. Mouth or jaw hooking can reduce the likelihood of serious internal injury to the fish. which can help it survive.




J HOOK



J Hooks vs. Circle Hooks
Comparing catches of fish caught on circle hooks and "J" hooks, Prince et al (2002) found catches per unit of effort (how many fish were caught for a given number of hooks fished) were approximately equal for Pacific blue marlin and were higher on circle hooks for Pacific sailfish. While not statistically significant, Skomal et al. (2002), also found that catch rates of bluefin tuna were slightly higher for circle hooks than for "J" hooks.

[Bluewater Sportfishing]

holy shit that is a long post
Fin,
It seems you guys have done your homework with the hooks. well there is my answer to the 179 fish. I figured the fight time was nothing but all those hooks. damn what did you guys have 1-2 guys just re-rigging lines all day long? talk about sore fingers.

[Finnseeker]

holy shit that is a long post
Fin,
It seems you guys have done your homework with the hooks. well there is my answer to the 179 fish. I figured the fight time was nothing but all those hooks. damn what did you guys have 1-2 guys just re-rigging lines all day long? talk about sore fingers.

Copy that we had 2 guys rigging snelling fulltime all day and just handing a fresh rod over each time ready to go.

Sorry about the long post but best to share facts for all to read and see