Pulpos y cautividad -Applications in the experimental octopus fishery-

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Este borrador es un informe del Departamento de medioambiente y turismo de la República de Sudáfrica.
Explica algunas de las pautas a seguir para la cría y pesca de pulpos.

1. Introduction
The common octopus Octopus vulgaris, which is intended to be the species of octopus for which experimental fishing permits are to be allocated, is an under exploited resource in South Africa. At present, in South Africa this species is only harvested in the intertidal during spring low tide for use as bait, whereas the same species is considered a delicacy in many countries including Japan, Portugal and Spain.
It is the intention of the Department of Environmental Affairs and Tourism: Branch Marine and Coastal Management to begin the process of determining the feasibility of developing a twenty third South African commercial fishery – a commercial octopus fishery that will sustain the harvesting of sufficiently large quantities of octopus using sustainable catching methods and to export harvested octopus to countries that consider this resource a delicacy for human consumption.
The Department therefore intends inviting prospective applicants to make application to it on the specimen application form attached so that a partnership of research into the viability of an octopus fishery and the possible development of a directed commercial fishery may begin between an anticipated 16 successful applicants and the Department.
It is important to note from the outset that this draft policy is intended to guide the evaluation of applications for permits to participate in the experimental octopus fishery.
The weighting, if any, to be attached to the criteria will be determined by the Department once it has received all properly lodged applications. Applicants will be informed of this weighting once permits have been awarded to the successful applicants.

2. Background to the Octopus vulgaris species
Octopuses belong to the class Cephalopoda and are closely related to squid and cuttlefish. These animals have been harvested by artisanal fisheries since classical times and currently form an important component of the total fish landings in Portugal, Spain, Japan, Mauritania and Mexico. Octopuses are ideal candidates for commercial exploitation as they are short-lived, fast growing and have firm textured meat with a high meat recovery of 70-85%.
Octopuses may be caught in a variety of ways, including diving, trawling, spearing, long-lining using hooks and long-lining using pots. The latter has proven to be the most efficient technique in catching octopus by small-scale / artisanal fisheries in other parts of the world and hence accounts for the highest landings of octopus worldwide by these directed fisheries. The successful permit applicants will only be entitled to harvest octopus by means of long lining using pots.
A total of 39 species of octopus have been identified in South African waters. Of these, two species are significantly exploited, namely the common octopus Octopus vulgaris and the giant octopus Octopus magnificus. O. vulgaris occurs along the entire coastline of South Africa and is found from the intertidal to depths of over 200 m. It is currently only harvested in the intertidal during spring low tides by artisanal fisheries. As noted above, this species, although it has a high commodity value as a food species, is mainly used as bait. In contrast, O. magnificus is a deepwater (100 – 300 m) species and is caught as a by-catch in bottom trawl nets, south coast rock lobster traps and hake long-lining fisheries operating along the south coast. This species is exported to foreign markets where it is also used as bait. Of the two species O. vulgaris is considered to be the most suitable for exploitation by small-scale fisheries, due to its accessibility in shallow water and higher market value.

3. The Purpose and Objective of the experimental Octopus fishery
First and foremost, it is the intention of the Department to develop a carefully planned and regulated experimental fishery that could possibly develop into a commercial fishery.
The purposes and objectives of allocating experimental permits in the octopus fishery comprise two primary and numerous secondary objectives.
The first primary objective is to assess the fishing technique using pots attached to long lines and to modify the methodology if necessary, thereby making it more suitable for conditions prevalent in South African waters. The second primary objective is to identify ways of conducting meaningful octopus stock assessments or ways in which to obtain abundance indicators of the stock so as to estimate a sustainable fishing effort for the resource.
The secondary objectives include economic and octopus population biology studies, which will be essential for effective management of a future commercial fishery if the experimental fishery is found to be viable.

4. Duration
It is the intention of the Department to grant permits in this experimental fishery annually for a period not exceeding five years. It is anticipated that within 5 years sufficient data will be collected by the Department from permit holders to determine the economic and environmental viability of developing a commercial octopus fishery in South Africa and to determine appropriate management strategies for such a fishery. It is important to note that although annually renewable for a period of five years, a failure by the permit holder to comply with one or more permit conditions could result in the refusal to grant a further permit.

5. Number of Permits to be allocated
The Department has identified eight potentially viable fishing grounds in which the experimental octopus fishery is to operate. Having regard to a number of factors, such as the high degree of risk posed by an experimental fishery, the capital investment required for a 5 year experiment, and the potential number of applicants, the Department intends allocating a maximum of 16 experimental permits for the octopus fishery.

6. The Landing Sites
The Department has identified certain fishing grounds as being potentially viable. The nearest landing sites to these grounds are as follows:
Saldanha Bay
Simonstown / Kalk Bay
Gordons Bay
Hermanus / Gansbaai
Arniston / Struisbaai
Mossel Bay
East London
Port Elizabeth

Priority will be given to those applicants domiciled or whose registered places of businesses are closest to these landing sites.

7. Harvesting the Octopus
It is proposed that at this stage the octopus should be harvested by means of pots using long lines. This method is currently considered to be efficient, effective and the by-catch will be negligible.
Pot fishing is a passive technique, which exploits the need for the octopus to seek shelter. Therefore no bait or active fishing is required. When the pots are retrieved by means of a hydraulic line-hauler, any octopus inside the pots will remain as their natural tendency is to cling to their immediate substrate when disturbed. Additional benefits of this fishing method are:
No by-catch will be landed; and
It preserves the quality of the octopus.

The permit-holders will only be entitled to harvest octopus by means of long lining using pots. Each experimental permit-holder will be restricted to 2 000 pots. Of these a minimum of 900 pots will be reserved solely for experimental fishing for the duration of the 5 years. The reserved pots should at this stage include 2 pot-types. The options are 110 mm diameter PVC pot and 150 mm diameter PVC pot or tyre pot and 150mm PVC pot. The situation may arise that subsequent to the commencement of the experiment, one or both of these above pot-type options may be changed by the Department. A total of 300 pots (150 of each pot-type) will be deployed per depth range. The number of pots to be attached to a main line (and hence the number of main lines) will be left to the discretion of the permit holder. These pots are to be attached in an alternating sequence to the main line. Main line(s) will be deployed parallel to the coast between 15 - 20 m depth. Similarly, another set (containing 300 pots) will be deployed further offshore at 20 - 30 m depth and a third set deeper than 30 m. The pots will be spaced 7 m apart on the main line in an attempt to minimise territorial conflict and cannibalism between octopuses in adjacent pots and hence resulting in equal probability of catching octopus in adjacent pots compared to catching octopus in non-adjacent pots. All pots used in this stringent experimental design will be numbered to determine the spatial distribution of octopuses.
The fishing area will be determined from sea charts and by consulting with experimental permit-holders. Any lost, stolen or damaged gear will be immediately replaced by the experimental permit-holder. This structured experiment will be used to determine the most efficient pot-type by season. Also by fishing simultaneously at different depths will give an indication of the seasonal onshore-offshore movements of octopus. As an observer will accompany the experimental permit-holder when lifting experimental lines, all catch rates will be verified and all octopuses caught will be weighed and sexes determined.
Furthermore, when lines are lifted, the first 15 animals caught at each depth zone will be retained for biological analysis. Hence, accurate data on depth, substrate type, GPS, catch rates, sex ratios, population size structure, diet, size at maturation and spawning seasons will be obtained.
Experimental lines should be retrieved approximately every 7 days (weather permitting and excluding weekends and public holidays).
As far as the remaining 1 100 pots are concerned, the experimental permit-holder will be allowed to choose any pot-type design. If the permit-holder chooses to use more than one pot design for the extra pots then for consistency of data, each main line should consist of the same pot-type (one pot-type per main line). No trap doors or baiting will be allowed. The experimental permit-holder may fish these pots in any manner it chooses, including changing pot spacing on a main line, soak times and depth of fishing, provided that fishers keep accurate records of the number of pots fished, the soak times, catches per pot type, depth fished, GPS position and substrate type. However, at no stage will the experimental permit-holder be allowed to deploy these pots within 1 mile of the experimental lines. At the harbour or slipway the entire catch will be weighed in the presence of a fishery control officer or observer and the fishery control officer or observer must be notified of any tagged animals. Although the lifting of additional pots will not be monitored on a regular basis spot checks will be conducted from time to time.
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