Seasonality, sex ratio, spawning frequency and sexual maturity of the opakapaka Pristipomoides filamentosus (Perciformes: Lutjanidae) from the Main Hawaiian Islands: fundamental input to size-at-retention regulations

2018 ◽  
Vol 69 (2) ◽  
pp. 325 ◽  
Author(s):  
Meagan A. Luers ◽  
Edward E. DeMartini ◽  
Robert L. Humphreys
Keyword(s):  
Sexual Maturity ◽  
Comprehensive Evaluation ◽  
Hawaiian Islands ◽  
Fork Length ◽  
Minimum Size ◽  
Recreational Fisheries ◽  
Median Length ◽  
Spawning Frequency ◽  
Stock Status ◽  
Body Sizes

The crimson jobfish Pristipomoides filamentosus (locally known as ‘opakapaka’ in Hawaii) is a deep-water eteline lutjanid that supports important commercial and recreational fisheries in Hawaii and throughout much of the Indo-Pacific region. It is one of the most commonly caught species of the ‘Deep-7’ bottomfish species complex in the commercial bottomfish fishery of Hawaii. However, there are currently no validated estimates of median body sizes at sexual maturity that can be used in a comprehensive evaluation of the species’ stock status within Hawaiian bottomfish fisheries. Herein we provide size-at-maturity estimates for the species in the main Hawaiian Islands: median length at maturity of 40.7-cm fork length (FL; 95% confidence interval (CI) 40.3–41.2cm) for females and 34.3cm FL (95% CI 33.3–35.3cm) for males, with respective equivalent median weight-at-maturity estimates of ~1.17 and ~0.70kg (2.58 and 1.55 lb). We suggest these newly available data be seriously considered in any future evaluations of minimum size regulations, currently set at ~0.45kg (1 lb) regardless of sex, for the species’ fisheries in Hawaii.

Body size at sexual maturity in the eteline snappers Etelis carbunculus and Pristipomoides sieboldii: subregional comparisons between the main and north-western Hawaiian Islands

2017 ◽  
Vol 68 (6) ◽  
pp. 1178 ◽  
Author(s):  
Edward E. DeMartini
Keyword(s):  
Life Histories ◽  
Sexual Maturity ◽  
Hawaiian Islands ◽  
Fork Length ◽  
Geographic Variations ◽  
The North ◽  
General Importance ◽  
Body Sizes ◽  
History Of ◽  
North Western

New estimates of median body length at sexual maturity (L50) are presented for females of ehu (Etelis carbunculus) and kalekale (Pristipomoides sieboldii) in the main Hawaiian Islands (MHI); these are compared with published estimates for females of each species in the north-western Hawaiian Islands (NWHI). This case study illustrates the general importance of identifying regional and subregional variations in species’ life histories when estimating parameters for input to stock assessments. L50 values differed somewhat between the two species, but greatly between the MHI and NWHI for each species. Size-standardised ovary weights were greater in the NWHI v. MHI for all-sized fish of both species and nominally greater at larger body sizes among the mature females of both species in the MHI compared with the NWHI. L50 was smaller in the MHI compared with NWHI for females of both species. The mean (±s.e.m.) L50 for female ehu was 23.4±0.3- v. 27.2±1.0-cm fork length (FL) in the MHI v. NWHI respectively. For female kalekale, the respective estimates were 23.8±0.3 and 28.6±0.7cm FL. Possible determinants of these subregional geographic variations in L50, including latitude, productivity and history of extraction by Hawaiian bottomfish fisheries, are discussed.

scholarly journals Growth and reproduction properties of endemic Capoeta kosswigi and Barbus ercisianus in the Deliçay Stream (Van, Turkey)

2021 ◽  
Vol 38 (3) ◽  
pp. 293-302
Author(s):  
Ataman Altuğ Atıcı ◽  
Ahmet Sepil ◽  
Fazıl Şen ◽  
Asude Çavuş
Keyword(s):  
Sexual Maturity ◽  
Condition Factor ◽  
Fork Length ◽  
Lake Van ◽  
Reproductive Characteristics ◽  
Lake Van Basin ◽  
Growth And Reproduction

In this study, the growth and reproductive characteristics of Capoeta kosswigi Karaman, 1969 and Barbus ercisianus Karaman, 1971, which are endemic to the Lake Van Basin, in Deliçay (Van) were investigated. A total of 309 C. kosswigi and 288 B. ercisianus specimens were caught by electrofishing between April and August 2018. The fork length of C. kosswigi and B. ercisianus ranged from 3.7-26.1 cm and from 4.3-22.7 cm, and the total weights ranged from 0.6-227.4 g and from 1.2-140.0 g, respectively. The most intensive catching was in C. kosswigi population of 5.0-6.9 (27.5%) cm and 0-19.9 (67.0%) g in the groups, and 12.0-13.9 (24.7%) cm and 0-9.9 (23.3%) g groups in B. ercisianus. Condition factor was determined as 1.305±0.008 (0.798-1.886) in C. kosswigi and 1.158±0.006 (0.864-1.559) in B. ercisianus. The length-weight relationships were calculated as W = 0.01435 × L2.952 (r2 = 0.996) for C. kosswigi and W = 0.01276 × L2.959 (r2 = 0.994) for B. ercisianus. The M:F ratio was calculated as 1:0.15 in C. kosswigi and 1:0.64 in B. ercisianus. It was established that C. kosswigi attained sexual maturity when they reached to 11 cm fork length for males, 18 cm fork length for females. Maturation of B.ercisianus individuals occurred at 9 cm fork length in males and 12 cm fork length in females. The spawning in C. kosswigi was observed from 1st week of May to 2nd week of July, and in B. ercisianus from 1st week of May to 1st week of August. It may be suggested that minimum catching size must be 20 cm fork length for C. kosswigi and 15 cm fork length for B. ercisianus.

scholarly journals Shore-based competitive recreational fisheries in southern Bahia, Brazil: A baseline study

2020 ◽  
Vol 33 (2) ◽  
pp. 183-203
Author(s):  
Katia Meirelles Felizola Freire ◽  
Felipe Pinto Nascimento ◽  
Gecely Rodrigues Alves Rocha
Keyword(s):  
Minimum Size ◽  
Current Status ◽  
Total Catch ◽  
Recreational Fisheries ◽  
Middle Aged ◽  
Baseline Study ◽  
Commercial Importance ◽  
Southern Bahia ◽  
Catch Composition ◽  
Main Factor

This study describes shore-based competitive fishing events in Ilhéus, southern Bahia (Brazil), including catch composition, and provides information on the profile of recreational fishers participating in these events. Information was collected in all events promoted by the Clube de Pesca de Ilhéus (CLUPESIL) in 2007-2008. A total of 26 competitive fishing events were organized during this period, with 47 species caught. The top species were: Cathorops spixii, Menticirrhus littoralis, Trachinotus goodei, Eucinostomus melanopterus, Polydactylus virginicus, Atherinella brasiliensis, and Eucinostomus argenteus. These seven species represented 87% of the total catch in number and 78% in weight. Menticirrhus littoralis and Polydactylus virginicus are species of commercial interest and their catch was dominated by juveniles. Local recreational fishers were predominately middle-aged men, who tended to use small hooks and mainly shrimp as bait. They were consumption-oriented, but also released small fishes. During competitions, fishers used even smaller hooks. Most of them perceived shrimp trawling as the main factor affecting recreational fisheries. The use of larger hooks and a minimum size of 20 cm are suggested to decrease the capture of juveniles, mainly those of commercial importance. This study sets a baseline from which new studies can be proposed to access the current status of local recreational fisheries.

Red Snapper: Ecology and Fisheries in the U.S. Gulf of Mexico

2007 ◽  
Keyword(s):  
Gulf Of Mexico ◽  
Fork Length ◽  
Red Snapper ◽  
Minimum Size ◽  
Minimum Length ◽  
Commercial Fishing ◽  
Lutjanus Campechanus ◽  
Commercial Harvest ◽  
Length Regulation ◽  
The U.S

<em>Abstract.</em>—Red snapper <em>Lutjanus campechanus </em>were sampled from commercial landings from the Gulf of Mexico (GOM) off Louisiana from October 2001 to May 2004. Fork length (FL), eviscerated weight, otoliths (both sagittae), and sex determinations were taken from 2,900 specimens; FL was subsequently converted to total length (TL) with the equation TL = 1.073 (FL) + 3.56. Red snapper ages (<EM>N </EM>= 2,867) estimated from counts of opaque annuli in otoliths ranged from 1 to 14 years; however, the vast majority (97.7%) of these were ages 2 to 6 years and the modal age was 3 years. Total lengths among 2,897 specimens ranged from 278 to 940 mm, modal TL was 400 mm, and 98% of all specimens were less than 600 mm TL. We also investigated the fate of red snapper regulatory discards (individuals <381 mm [15 in] TL) during 16 trips on working commercial vessels; over two-thirds of 4,839 red snapper assigned among four discard fate categories (ranging from alive and vigorous to dead) were returned to the water either in moribund or dead condition. Among 399 potential discards retained for age and length analyses, 86% were between 12 and 15 in (305–381 mm) TL and 85% were 2 years of age. The minimum size regulation appears to do little to protect juvenile red snapper from commercial fishing mortality. Heavy red snapper mortality, which begins as bycatch mortality in shrimp trawls, continues as discard mortality at sub-legal lengths when they first recruit to the offshore fishing grounds, and persists as harvest mortality among the youngest legal year- and size-classes. If the minimum size limit is intended to provide a respite from such mortality, a reconsideration of the utility of the minimum length regulation in the commercial harvest of red snapper may be warranted.

Paddlefish Management, Propagation, and Conservation in the 21st Century

2009 ◽  
Keyword(s):  
Fork Length ◽  
Handling Time ◽  
Minimum Size ◽  
Fish Length ◽  
Fishing Mortality ◽  
Reasonable Approach ◽  
Radio Transmitters ◽  
Early Fall ◽  
Delayed Mortality ◽  
Size Limits

<em>Abstract</em>.—We present information on delayed mortality of commercially exploited paddlefish <em>Polyodon spathula </em>released as bycatch in Kentucky Lake, Tennessee–Kentucky, an impoundment on the lower Tennessee River. Minimum size limits enacted in 2002 (864 mm eye-to-fork length [EFL]) and 2005 (914 mm EFL) sought to protect paddlefish from overfishing. In 2005, bycatch of sublegal paddlefish represented 75% of the total catch, and releasing undersized fish will not reduce fishing mortality unless those fish survive. Paddlefish caught and released by commercial fishers in 2005 and 2006 were externally tagged with radio transmitters and tracked a minimum of 2 weeks to estimate delayed mortality. Four of the 104 tagged paddlefish died following release, 94 survived, and 6 were censored because their fate could not be determined. Paddlefish that survived moved rapidly from release locations. Net movements of the 94 fish that survived averaged 12.0 km (SE = 5.3) upriver and ranged from 91.5 km downriver to 390.0 km upriver. Fish that died could not be distinguished from fish that lived on the basis of mean water temperature, fish length, net-soak time, or handling time. Given the low delayed mortality of discarded paddlefish, imposing minimum size limits is a reasonable approach to reduce fishing mortality of juveniles and reduce the likelihood of overfishing. Efforts to reduce fishing mortality should focus on avoiding fishing gear and seasons (e.g., early fall and late spring) that cause high initial bycatch mortality.

scholarly journals Fin Length and Total Length Relationships of Silky Shark Carcharhinus falciformis Landed at Tanjung Luar Fish Landing Port, West Nusa Tenggara, Indonesia

2020 ◽  
Vol 147 ◽  
pp. 02011
Author(s):  
Selvia Oktaviyani ◽  
Wanwan Kurniawan ◽  
Fahmi
Keyword(s):  
Sexual Maturity ◽  
Minimum Size ◽  
Pectoral Fin ◽  
Dorsal Fin ◽  
Total Length ◽  
Length Relationship ◽  
Silky Shark ◽  
Valuable Product ◽  
The Relationship ◽  
Fin Length

Shark fins are a very valuable product for international trade. This study aims to obtain the equations describing the relationship between fin length and the total length of silky shark. Using the total length at sexual maturity (Lm), the equation is then used to estimate the fin length associated with this Lm, which can then be included in the recommendation for international shark fin trades. Data collection was carried out from March 2018 to February 2019 at Tanjung Luar Fish Landing Port, West Nusa Tenggara. All data were collected from 2,837 individuals of silky sharks, consisting of 1,416 females and 1,421 males. The total length of silky shark ranges from 61 to 282 cm for females and 18-283 cm for males. The relationships of first dorsal fin length and total length is DFL=2.0151+0.1243 TL (both sexes). Furthermore, the relationships of pectoral fin length and total length were found to be PFL=-8.0098+0.2127 TL (both sexes). The first dorsal fin length and pectoral fin length at the time the silky shark sexually matures were 23 cm and 35 cm, respectively. This fin-total length relationship can be used by the fisheries authority to determine the allowed minimum size of silky shark fins for export.

Contribution of stocked fish to riverine populations of golden perch (Macquaria ambigua) in the Murray–Darling Basin, Australia

2016 ◽  
Vol 67 (10) ◽  
pp. 1401 ◽  
Author(s):  
David A. Crook ◽  
Damien J. O'Mahony ◽  
Bronwyn M. Gillanders ◽  
Andrew R. Munro ◽  
Andrew C. Sanger ◽  
...  
Keyword(s):  
Minimum Size ◽  
Recreational Fisheries ◽  
Catch Per Unit Effort ◽  
Age Classes ◽  
Murray Darling Basin ◽  
Murray River ◽  
Native Fishes ◽  
Release Location ◽  
Three Rivers ◽  
Natural Recruitment

Stocking of native fishes is conducted to augment riverine fisheries in many parts of the world, yet most stocking activities are conducted without empirical information on their effectiveness or impacts. In the Murray–Darling Basin (MDB), Australia, stocking has been underway for several decades to maintain recreational fisheries. We stocked chemically tagged golden perch (Macquaria ambigua) fingerlings in three rivers to determine the proportions of stocked fish within populations of the species. Stocked sites were monitored for up to 5 years in the Murrumbidgee River, Edward River and Billabong Creek and non-stocked sites were monitored in the Murray River. Catch per unit effort of stocked year classes increased substantially in Billabong Creek, with stocked fish contributing 100 (2005), 79 (2006) and 92% (2007). Chemically tagged fish comprised 18–38% of the respective age classes in the Murrumbidgee and Edward rivers and there was little evidence of natural recruitment in the non-stocked Murray River. Tagged fish generally attained the legal minimum size within 4 years and had dispersed up to 60km from the original release location. Our results demonstrate that artificial stocking has the potential to strongly influence the abundance and population structure of golden perch in rivers of the MDB.

scholarly journals PENDUGAAN UKURAN PERTAMA KALI MATANG GONAD IKAN KEMBUNG (Rastrelliger sp) DI PERAIRAN DESA SIDANGOLI DEHE KECAMATAN JAILOLO SELATAN KABUPATEN HALMAHERA BARAT

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Salim Abubakar ◽  
Riyadi Subur ◽  
Irmalita Tahir
Keyword(s):  
Random Sampling ◽  
Fork Length ◽  
Minimum Size ◽  
Gonad Maturity ◽  
Gill Net ◽  
First Time

Abstrak:Tujuan dari penelitian ini adalah untuk mengetahui ukuran pertama kali matang gonad dan ukuran mata jaring gillnet untuk penangkapan ikan kembung (Rastrelliger sp) di perairan Sidangoli Dehe. Pengambilan sampel dengan mengikuti kegiatan operasi penangkapan.dengan nelayan. Operasi penangkapan ikan dilakukan sebanyak 2 kali setiap minggu dan dilakukan selama satu bulan. Hasil tangkapan diambil secara acak (random sampling). Hasil tagkapan selanjutnya dilakukan pengukuran panjang cagak dan body girth. Penentuan tingkat kematangan gonad (TKG) yang dilakukan secara visual dengan melihat bentuk, warna serta perkembangan isi gonad.Hasil penelitian diperoleh ukuran pertama kali matang gonad ikan kembung (Rastrelliger sp) yang tertangkap di perairan Desa Sidangoli Dehe dengan kisaran panjang cagak 250,7 mm sedamgkan ukuran mata jaring insang minimum yang sebaiknya digunakan untuk penangkapan ikan kembung (Rastrelliger sp) yaitu 11,8 cm (4,6 inchi). Kata Kunci : Matang gonad, mata jaring, Rastrelliger sp, Sidangoli Dehe Abstract: The purpose of this study is to determine the size of first-time gonads and the size of gill-net for catching mackerel (Rastrelliger sp) in Dehe Sidangoli waters. Sampling by taking part in arrest operationswith fishermen. Fishing operations are carried out twice a week and carried out for one month. The catch is taken randomly. The result of the next tag is the measurement of the fork length and body girth. Determination of the level of gonad maturity (TKG) that is done visually by looking at the shape, color and development of gonadal contents. The results showed that the first size of mackerel gonad (Rastrelliger sp) that was caught in the waters of Sidangoli Dehe Village with a fork length of 250.7 mm was the minimum size of the gill-net which should be used for catching mackerel (Rastrelliger sp) which was 11.8 cm (4.6 inches). Keywords: Gonad mature, mesh, Rastrelliger sp, Sidangoli Dehe 

scholarly journals Patterns of temporal variation in growth rate from a mainland population of Anolis nebulosus (Squamata: Dactyloidae), in the Mexican Pacific Coast

2017 ◽  
Author(s):  
Aurelio Ramírez Bautista ◽  
Uriel Hernández-Salinas ◽  
Raciel Cruz Elizalde
Keyword(s):  
Growth Rate ◽  
Food Availability ◽  
Sexual Maturity ◽  
Pacific Coast ◽  
Growth Patterns ◽  
Dry Forest ◽  
Minimum Size ◽  
Von Bertalanffy ◽  
Mexican Pacific ◽  
Size At Sexual Maturity

In this study we used three nonlinear regression models: Von Bertalanffy, logistic-by-length, and logistic-by-weight to describe the pattern of growth of hatchling, juvenile, and adult of the lizard Anolis nebulosus in a tropical dry forest near of the Mexican Pacific coast during a period of 1989 and 1990. Von Bertalanffy and logistic-by-length models showed the best fit to the growth data for males and females of three age classes from marked and recaptured lizards in these years. The characteristic parameter of growth (r) and asymptotic growth (A1) extracted from these models indicated that males grow faster than females, but the latter reach a slightly larger size than males. The growth curves revealed that males reach minimum size at sexual maturity at 35 mm in snout-vent length (SVL), at an age of seven months, while females reach sexual maturity at 37 mm of SVL at nine months. Comparisons of growth rate between wet and dry seasons and years revealed that hatchlings and juveniles of both sexes had higher growth during the wet season for both years. Although there was no significant variation between measured environmental variables or in the food availability, the weight of evidence suggests that environmental variation has an influence on the growth of A. nebulosus of this population. Results indicate that variation on growth patterns observed may result from a combination of environmental factors, such as food availability, predation pressure and some reproductive characteristics as size at sexual maturity and size of hatchlings at birth.

Sign in / Sign up

Export Citation Format

Share Document