Does this mean whether demarcating special fishing zones would lead to over-fishing in these zones? Please clarify.

Dola please clarify the question....if your question is whether demarcation of potential fishing zones... yes there are more chances of over fishing. these are more evident in single species fisheries in temperate waters...as tropical waters we have depend on multi species fishery i think the impact would not be much worse (?).....there is not much work has been carried out in indian waters...but surely trawling have detrimental effects....

I just want to know if we demarcate an area as potential fishing zone (PFZ), are we encouraging over exploitation of commercial fish stocks over the area?

answer would be ..possibly yes...in temperate waters they have implemented quota systems...we dont have such regulations...so it can encourage the over fishing in the area......usually the PFZ notifications are mainly intended for catching shoaling fishes like sardines, mackerels and anchovies......these fishes have short life span and in my opinion we we can maintain the sustainability if we can implement some regulations such as quota systems and maximum harvestable yield.... but we can considerably reduce the scouting time (searching time) thus helps to minimise the fuel expenditure (carbon emission)

@Aneesh: What do you mean by quota system?

hope you are aware about TAC (total allowable catch). harvastable catch is restricted and catching more than the allowed quantity is treated as illegal. these are known as fishery resources management plans. we dont have such rules and regulations. as a multi species fisheries, it is very difficult to implement also. INCOIS is giving PFZ notifications to the fishermen of India and it found to be very effective. these notifications are for pelagic fishes as i mentioned early.

Thanks Aneesh for the information above. I would like to know how these notifications have helped the fishermen in India? especially when the competition for fishery resources in Indian waters is comparatively higher than those of north Atlantic seas where species-specific fishery is practiced more. Would these notifications also indirectly help biodiversity conservation ?

In the same line with Anant, I wish you give us some details on how the notofications are helping Indian fishers and the fish-stocks in general.

friends

INCOIS is giving PFZ notifications for the fishermen of India. They have installed a digital display board in main centres usually fishing harbours, main junctions, fisheries offices etc. the fishermen can take down the lat long positions from the display board. these PFZ notifications are not much intended for biodiversity conservation. it is for reducing the searching time and for improve the catch. reduced searching time can considerably reduce the carbon emission.

Thanks Aneesh. I think demarcating these zones will also indirectly help reduce the by-catch as well as reduce the pressure on already depleted stocks in the overfished zones. As you said it, carbon emission will also decrease from reduced search time.

I am curious to know how these PFZs are actually located? Is it taken from the FSI survey data or from ecological habitat modelling for the commercial fishes?

I would also like to thank Dola for initiating such an informative discussion.

Dear Pande

your first statement (by-catch reduction) is correct to some extent because it encourage the targeted fishing. but it will not reduce the pressure on already depleted stocks. it actually enhance the catch. so there are some opinions that PFZ notification can cause resource depletion.

PFZ are actually located by using satelite imagery. chlorophyll and seas usrface temperature (SST) are the main oceanographic parameters used for predicting the PFZ

If 100 % of the mechanized and motorized boats operating over an area use PFZ advisories; although this will account for annual savings in crores just on account of diesel savings in addition to the valuable human effort, isn’t it is of concern that in few years commercial fish stocks in our waters will vanish. Isn’t its necessary at this stage to adopt some kind of PFZ-Management strategies to conserve fish biodiversity and stocks? If every fisher along a coast runs to harvest fishes from a PFZ, wont it result in over-exploitation of commercial fish stocks over the area?

I mentioned during our early discussion for the need of some management measures and regulations like quota systems.

This PFZ is not a fixed place like marine biodiversity reserve. It may shift from place to other according to the oceanographic parameters.

SST functions for only 2 to 3 days after the data is downloaded,beyond which it is ineffective.Certain maritime states have their own fishing rules in order to have sustainability.For e.g.Kerala doesn't allow mechanized vessels to operate within 5 KMs coastal zone.Other states do have closed fishing seasons, coinciding with fish breeding season. But the point here is the authorities can't effectively monitor any part of fishing activity,thereby leaving the area to be free for all.To compound the problem,foreign vessels say from Taiwan do fish in potential zones & get scot free - due to laxity in monitoring.Moreover in the name of catching fish wherein fish trawl is to be used,almost all the trawlers use shrimp trawl,smothering the benthic structure of sea beds.The cod end mesh size is so small that even baby fishes get caught to the extent of 80% of the total catch of the trawlers.This waste doesn't even fetch any price & being a waste,directly hits future stock.The fishermen are so cleaver that they know each of the potential fishing zones among them selves & they don't depend on any advices from authorities.

So as I understand, the situation is worrying.

1) The situation is beyond redumption,as I have still to point out some more facts.For e.g.fishing trawlers in some areas use 1.5 times the engine power than is actually required as per the size of the boat.When I asked as to the reason,they say that more power means higher speed for the trawler to drag the net which means more shrimp catch.Another reason they say is they don't have time to repair engine during its failure if it happens in peak fishing season- as it leads to lesser fishing hours.Hence they are using more diesel than is actually required & more so because every year as the efficiency of engine goes down,if they had used engine of lower power,then after some years,the speed of the boat would be lessened,which entails a loss to them.Hence as the Govt. has been supplying subsidized diesel,there is still profit for them in spite of their using high engine power.This fact is over looked by authorities.

2) Some of the fishermen go for fishing as far as Iran waters & always land bumper catch - as those waters are still underfished & out of these some get caught by our neighbour - still knowing that they would languish in their jails for many years.If there were still lucrative fishing zones in our waters,- would these fishermen would have gone to other countries & invite trouble.

This indicates that there are lot to be done in this aspect. As I visited and talked with the researchers in a pioneer RS-GIS institute in the country regarding the issues, very recently, I was informed that there are departments in the Govt. that are taking care of sustainability and that is all they said. No further information I could gather from the people who are involved in the process of demarcation of PFZ in the Indian limits. I am not sure if the problem is well understood by the authorities!

Could anyone help me to find out the accuracy of Potential Fishing Zone (PFZ) advisory.

I want to know about how others are validating the PFZ advisory for Potential Fishing area and how you are correlating the In-situ and Ex-situ data.

I also want to know the what type of gear i.e. Trawl etc using for fishing.

Please let me know some valuable suggestion which will help to carry out my research work.