Australian Politics Forum - Marine Parks as a Fisheries Management Tool

pjb05

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Re: Marine Parks as a Fisheries Management Tool
Reply #255 - Feb 25^th, 2009 at 7:42pm

Here's an example of scientists doing what scientists are meant to do:

COMMENT
Burdens of evidence and the benefits of marine reserves:
putting Descartes before des horse?

An extensive literature has appeared since 1990 on the study of ‘no-take’ marine reserves and their potential to make significant contributions to the conservation and management of fisheries,
especially in tropical environments (see Polunin 1990; Roberts & Polunin 1991; DeMartini 1993; Roberts 1997; Allison et al. 1998; Guénette et al. 1998). The literature describes many potential
benefits of marine reserves to fisheries, including increases in spawner-biomass-per-recruit and increases in larval supply from protecting ‘source’ populations ( Jennings 2000). The important
word here is ‘potential’. Some claims made by advocates of marine reserves might be regarded as optimistic, whereas critics of reserves might sometimes have been unduly harsh. Conservation
goals for marine reserves are often poorly defined, and differences of opinion regarding the efficacy of reserves for fulfilling any of their stated goals can frequently be attributed to a lack of good
information with which to predict their effects. Here, we critically examine the literature from 1990–2001 to determine (1) the relative effort put into empirical and theoretical approaches to
predict reserve effects, and (2) the quality of empirical evidence available to support theoretical predictions. It is not the purpose of this article to single out particular studies for criticism
(although this is sometimes inevitable to provide examples), nor to draw conclusions concerning the efficacy of marine reserves.

Our purpose is to examine the science, rather than politics, of the field of ‘marine reserves’. We examined the relevant peer-reviewed primary literature from 1990–2001 by searching the Current
Contents and Science Citation Index (ISI) databases using the keywords ‘marine reserve’ found anywhere in a paper. Also included were papers that were not in the search databases but were
cited in papers that were (these included refereed proceedings of symposia, but excluded book chapters and unpublished reports). Only studies that directly investigated the effects of reserves
were included. Many articles that explored specific biological issues mentioned marine reserves incidentally in the discussion. These were removed from the analysis, as were those concerned
solely with policy, management or advocacy. The remaining papers (n
205) were classified into three groups, namely empirical (presenting field data from existing reserves), theoretical (conceptual
or numerical modelling studies) and review (including notes and ideas papers based on other literature). With few exceptions, empirical papers reported some positive impact of the marine
reserve or reserves under study, so these were carefully examined to determine (1) the robustness of the survey design, and (2) the effect size.

Approaches to reserve study: trends in the literature
We found that the number of empirical field studies has been climbing at a fairly consistent rate over the last ten years, but has recently been lagging behind the combined publication rate of
reviews and theory (Fig. 1). Reading the latter papers, it is apparent that much of their raison d’être is advocacy for the establishment of marine reserves in parts of the world that lack them, rather
than real attempts to contribute to the science of the field. The difference between science and advocacy in this field is becoming increasingly blurred (Polunin 2002), and we may soon be in the
unusual situation of being faced with a greater number of reviews than there is reviewable material.The amount of attention given to theoretical work has also increased markedly since 1997.
Despite the increasing number of fisheries models that infer potential consequences of marine reserves (see Polacheck 1990; Dugan & Davis 1993; Rowley 1994; Allison et al. 1998; Bohnsack
1998), published evidence to empirically judge these models and their underlying assumptions is considerably rarer than might be expected.

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pjb05

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Re: Marine Parks as a Fisheries Management Tool
Reply #256 - Feb 25^th, 2009 at 7:48pm

We regard science as a process for learning about
nature in which competing ideas about how the world works are tested against systematic observations and experiments (Feynman 1985; Hilborn & Mangel 1997). Unfortunately, because of this dearth of data the models have little opportunity to compete against one another under the scientific process. Furthermore, the proliferation of models and reviews has resulted in model assumptions evolving into accepted paradigms, a case of ‘What everybody says must be true’
(Simpson 1993).The speculative conclusion that marine reserves will be effective management tools can be obtained from simple behavioural and demographic assumptions. These include:

(1) Where movement range of individuals is small relative to the size of the reserve, those individuals are spatially isolated from fishing mortality, and density within the reserve will be higher than in comparable fished areas.
(2) Elevated densities within the reserve will result in net emigration of biomass from the reserve to fished areas, either by random diffusion (Beverton & Holt 1957) or density-dependent
processes (specifically ‘spillover’) (Kramer & Chapman 1999).
(3) Unfished populations of fishes are composed of relatively larger individuals, which have greater fecundity, and hence reserves will act as more productive sources of gametes than comparable fished areas.
The magnitude of the effect may also be speculated on in some cases. For example, if adult fish are sedentary then it could be postulated that density in reserves will increase to carrying capacity
(see Hastings & Botsford 1999).

While such speculations are intuitive, they often appear in the literature as logically true assertions. However, these deceptively reasonable speculations are each dependent on underlying
assumptions about behaviour, ecology and the fishery. It is logically true that preventing fishing in particular areas will eliminate direct fishing mortality and stop the destruction of habitat caused
by contact fishing gears (Collie et al. 2000). However, it is imprudent to make untested assertions about the primary consequences of reserve protection on fish population dynamics, and then to
extrapolate those effects to fishery-level predictions. Typical predictions of fishery enhancement could be invalidated for a number of reasons, including displaced fishing effort around the reserve
boundary (Parrish 1999), recruitment limitation (Doherty & Fowler 1994), self-recruitment rather than larval export (Leis 2002), irreversible changes in species assemblages, and any number of
unknown causes due to the underlying complexity of the ecosystem. Without empirical substantiation, predictions of fishery enhancement are deductions based on circumstantial evidence and
ancillary information. Furthermore, even if model assumptions are logically correct, it is not sufficient to test only for the existence of reserve effects. Of real relevance is the magnitude of an effect and the certainty (or lack thereof ) that surrounds estimates of it.

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pjb05

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Re: Marine Parks as a Fisheries Management Tool
Reply #257 - Feb 25^th, 2009 at 7:56pm

We use the issue of recovery of density within reserves (assumption 1 above) as an example of how little evidence exists to substantiate the basic responses of fish populations to reserve protec-tion. We note here that this does not mean to imply that reserves fail in their objectives (we have ourselves documented large responses of exploited fishes to reserve protection), but that the quantity
of good scientific evidence is not as extensive as a cursory examination of the literature might indicate.

Many recent papers contain statements within their introductions along the lines of ‘It is well known that exploited species exhibit increases in density and mean size within reserves’, supported by a number of citations. A closer look at the cited papers shows that many are review articles (which themselves rely on reference to earlier reviews such as Roberts & Polunin 1991; Rowley 1994). Of the empirical studies cited, most present ambiguous evidence for recovery (see Jones et al. 1993; Rowley 1994; Edgar & Barrett 1997).
Detection of recovery of fish density in marine reserves often suffers from lack of rigour in the design of field surveys (Hurlbert 1984; Stewart-Oaten et al. 1986; Underwood 1990, 1993). As
Underwood (1990) pointed out, studies lacking replication cannot be logically interpreted. In the marine reserve context there are many reasons why researchers might have limits on their
sampling designs. However, a critical evaluation of the experimental designs employed by many published studies brought to light the following problems with replication and lack of control sites:
(1) insufficient sample replication (for example only one site sampled inside and outside a reserve, or no control sites sampled at all);
(2) spatial confounding (for example all control sites located only at one end of the reserve, so that comparisons are confounded by unknown location effects);
(3) lack of temporal replication (most studies consist of surveys done at only one time);
(4) lack of replication at the reserve level limiting the generality of results (although in many cases
this reflects the number of reserves available); and
(5) non-random placement of reserves, i.e. often reserves are sited to include ‘special’ or unique
features, which causes difficulties in selecting valid control sites (this is obviously no fault of the researchers).
To date, there are no well-designed studies that avoid the above problems as well as possessing a time series of ‘before’ and ‘after’ data. However, some might be used as examples of attempts to
fulfil good design criteria (Table 1). In addition, the power to detect effects can be affected by the choice of sampling method (Willis et al. 2000), especially when the target species are large carnivores
that can exhibit fishing-related behavioural plasticity between sites (Cole 1994; Jennings & Polunin 1995; Kulbicki 1998).
Traditional approaches to fisheries stock assessment are often unable to provide useful predictions because of the lack of information in the data, and the resulting inability to verify model assumptions or to accurately estimate model parameters (Ulltang 1998).

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pjb05

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Re: Marine Parks as a Fisheries Management Tool
Reply #258 - Feb 25^th, 2009 at 8:01pm

Indeed, such models can not reliably estimate sustainable levels of harvest without first overexploiting the resource, and this arises from the impossibility of performing controlled and replicated experiments on a large scale (Ludwig et al. 1993). There seems to be a trend to approach the issue of marine reserves in a similar fashion, partly because most countries so far have few of them. This is unfortunate,
because a marine reserve is a large-scale manipulation that can be assessed in a more rigorous, less equivocal fashion. It will, however, require good lines of communication between management
agencies and scientists; studies should begin well in advance of reserve implementation, and there must also be a commitment from management agencies to ensure compliance with reserve regulations
(Paddack & Estes 2000).

How many studies unambiguously demonstrate significant within-reserve increases in the density of exploited species? Edgar and Barrett (1997) recognized that, with a sufficiently large
sample size, a statistically significant difference between two sites (separated either spatially or temporally) can almost always be obtained due simply to true natural biological variability between
the sites. That is, the null hypothesis of no difference between two biological entities is necessarily false. They therefore proposed a 100% increase in density as a minimum criterion for claiming the
existence of a ‘reserve effect’. This type of approach is more generally known as bio-equivalence testing, in which an effect is not considered biologically significant unless it exceeds a pre-specified
threshold (McBride 1999). If we use the 100% threshold, and ignore flaws in sampling design, then there were only a handful of instances where differences in density of individual species between reserve and fished areas can be regarded as biologically significant (Polunin & Roberts 1993; Francour 1994; Harmelin et al. 1995; Russ & Alcala 1996; Edgar & Barrett 1997, 1999; Willis et al. 2003). In many other cases, slight trends towards higher reserve densities were
described, but these were of insufficient magnitude to confidently attribute them to reserve effects, rather than real biological variability at the spatial or temporal level (Roberts & Polunin
1992; Chapman & Kramer 1999; Paddack & Estes 2000). If we consider only those studies that are replicated in both time and space, to our knowledge there are only a few that establish increases
in excess of 100%: Ferreira and Russ (1995), Wantiez et al. (1997), Edgar and Barrett (1997, 1999), the long term studies of McClanahan (for example, McClanahan & Arthur 2001), and Willis et al. (2003).
Several theoretical studies have indicated that marine reserves can provide increases or equivalence in yield under the assumed model and parameter values (Polacheck 1990; DeMartini 1993;
Attwood & Bennett 1995; Sladek Nowlis & Roberts 1999). However, if management decisions are based upon models built on unquestioned assumptions then we may find ourselves making costly
errors. We reinforce this point by noting that the model of Parrish (1999) produces a contrary result; it suggests that the large reserves that are believed to be required to contribute to the Californian groundfish fishery might actually be to the detriment of the fishery, due to the displacement of fishing effort onto the remaining fishing grounds. In contrast, Horwood et al.
(1998) conclude that reserves will have little effect on fishery yield. Yet, the model of Hastings and Botsford (1999) concludes that, even with arbitrarily high fishing effort outside of large reserves,
marine reserves will return fisheries yields equivalent to traditional fisheries management for a wide variety of groundfish. Taken together, the conflicting conclusions from various plausible
models lead us back to the beginning, where we must admit that, at present, we cannot predict what the effects of marine reserves might be.

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Re: Marine Parks as a Fisheries Management Tool
Reply #259 - Feb 25^th, 2009 at 8:06pm

Concluding remarks
It is ironic that we must appear to bemoan the proliferation of marine reserve comments and reviews by writing yet another comment. However, the intention is not so much to complain about
such activities (very useful ideas have been published in this way), but to highlight the imbalance in research effort brought about by a lack of rigorous empirical science. Theoretical models (mathematical
or not) are useful in developing our ideas, but they are just that: ideas. Returning to the philosophical reference in the title, just because ‘we think’, does not mean ‘they are’. Indeed, it
would appear that a lot of thinking has gone into specification of competing models of marine reserves. That is, the models and prior hypotheses about the nature of marine reserves have been
put forward in abundance. It is now time to test them with data.

This comment is not intended to imply criticism of those working for the establishment of marine reserves, and it is not intended to counteract the precautionary principle (Lauck et al.
1998). Nor should this comment be interpreted as ‘anti-reserve’; our own research has demonstrated the potential of reserves for science and conservation (Babcock et al. 1999; Willis et al.
2000, 2003; Shears & Babcock 2002, 2003). Rather, it is a plea for researchers to apply the same rigour to examination of the fisheries-related efficacy of marine reserves as they would apply to
other environmental effects studies. Perhaps more importantly, this plea also goes out to those in a position to fund this research. They must ensure that adequate planning and resources are allocated
to make it possible to implement rigorous survey designs, and that this is done far enough in advance of reserve establishment so that effects outside their boundaries can be detected. In the
meantime, advocates might more convincingly point to the use of reserves as controls for the understanding of ecosystem function (Babcock et al. 1999; Pinnegar et al. 2000; Schroeter et al.
2001; Shears & Babcock 2002).

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freediver Gold Member Offline www.ozpolitic.com Posts: 49572 At my desk.	Re: Marine Parks as a Fisheries Management Tool Reply #260 - Feb 25^th, 2009 at 10:20pm PJ, you can't expect people to take you seriously if you dismiss the vast majority of scientific work in the field, because some of the scientists get paid, then pull out the same old dubious appeal to scientific authority.
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Re: Marine Parks as a Fisheries Management Tool
Reply #261 - Feb 26^th, 2009 at 5:59am

freediver wrote on Feb 25^th, 2009 at 10:20pm:

PJ, you can't expect people to take you seriously if you dismiss the vast majority of scientific work in the field, because some of the scientists get paid, then pull out the same old dubious appeal to scientific authority.

What a tepid argument. If you read 'Burdens of Proof' then you would understand that 'the vast majority of scientific work in the field' is actually a rather small body of empirical work. A lot of the so called science consists of reviews and models. Many state reserve benifits as though they are facts and cite references which turn out to be other reviews and these in turn refer back to earlier reviews! What empirical evidence there is lacks rigor in most cases. Burdens of proof points out that the line has been crossed to advocacy by many in the field, as did Prof Ray Hilborn. It is therefore valid to point out that many scientists who are enthusiastic about marine parks also happen to receive generous funding from Pew.

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Yadda

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Re: Marine Parks as a Fisheries Management Tool
Reply #262 - Feb 26^th, 2009 at 8:24am

pjb05 wrote on Feb 24^th, 2009 at 2:37pm:

They (marine sanctuaries) would never have got this far if they weren't a superficially appealing idea.

Yup!

I admit it, this idea does sound superficially appealing to me. Wink

But i also admit, i'm coming at this from the standpoint of a non-expert, and as a person without an 'interest' to defend.

It does seem logical, that in no-take areas [marine reserves] that are not subject to fishing, a natural, and a stable population of 'base' breeding stock population of fish would result?

If this is occurred, wouldn't this circumstance be a good thing?

I also understand [i remember this from a TV doco] that some species of fish need to attain a certain age / size before they start to breed.

With a practical need to protect a breeding stock population in all fisheries, surely such no-take areas [marine reserves] would be a very natural way, to help to facilitate the continuation of stable 'base' breeding stock populations, of many fish species?

Alternatively, if we [in Australia] decided to manage 'open' fisheries, which are always under [fishing] pressure, and [as a management strategy] we continue to take out the largest fish [i.e. much of the breeding stock population], is that smart, or is that dumb?

Quote:

However if the idea is to sutainable use the marine resource then the jury is out as to whether they are any better than traditional methods of quotas, limits on the no of commercial licenses, trip limits, closed season etc. If you look at the field evidence then the countries with the most sustainable fisheries have got there by relying on the latter - not marine sanctuaries.

pjb,

I'm coming to this topic as layman.

I admit, i have no deep knowledge of fishing regulations in Australia, and how effective they are [have been?], in protecting local fisheries.

Quote:

Then there are all the problems with marine reserves. There is a huge socio-economic fall out on coastal towns affected by them.

Hey, 'Life's a bitch.' when someone is standing between you, and making a dollar. Wink

But i think that we can both agree that a 'huge socio-economic fall out' [for ourselves] is no good reason to rule out a fisheries management system which could help fisheries to be more sustainable?

After all, any un-sustainable fishing practices [in any particular area] would also mean, 'a huge socio-economic fall out on coastal towns',
....when a fishery collapses due to over fishing [which has happened, in some northern hemisphere fisheries]?

But i do agree, that a fisheries management system which equates with 'best practice' should be sought out / determined on the evidence.

Quote:

The angling experience is degraded by the loss of most of the good fishing spots, overcrowing of those remaining, difficulty in complying (trying to keep track of lines drawn in the water), heavy fines or worse for usually innocent errors.

Most ppl have access to GPS technology today - so why don't they know that they are fishing [from a boat] within a 'posted' marine sanctuary?

Allow a warning to be issued, for a 1st offence, with a 'cancelled' fine?

And on a 2nd offence [within 6 months], issue fines for both the 2nd & the 1st offence?

Quote:

People have bought houses by the beach with the idea of throwing a line only to have fishing banned there when a marine park was declared!

That is hard [....the after the fact declaration of a marine park].

It could alleviate a lot of these problems [for existing residents] if authorities tried [where possible] to limit declaration of marine parks to offshore, and uninhabited shoreline areas?

Is that suggestion realistic?

Would it be possible to allow, within a marine park, shore based line fishing [having only a very localised, minimal impact?], but no boat fishing [and no spear fishing]?

Fighting cod war taught Icelanders the lesson of conservation
16 August 2000
.....For Britain the issue was jobs on Humberside, but for Iceland it was national survival. Before anyone else, islanders realised what a terrible problem overfishing would cause.
.....The science of limiting fish catches so as to maintain renewable resources for future fishermen was, to start with, poorly developed.
.....And, as in the European Union, which also claims to manage its resources, there is always political pressure to allow extra catches.....
.....Nearly 25 years on, Iceland is seen as a shining example of how stocks can be managed, even though the system is still not perfect. Each vessel carries its own quota of fish, catches must be carefully logged, and it is a matter of pride to stick to the rules, knowing thereby that fishermen are providing for their own future.
There are extensive nursery areas that are permanently closed to fishing.
.....In the North Sea, because there are no safe havens, few fish of spawning age are spared, hence the parlous state of stocks. Some believe cod will disappear altogether.
.....The answer is to take a lesson from Iceland and control stocks on a strictly scientific basis with proper zonal management.

http://www.guardian.co.uk/environment/2000/aug/16/fish.food1

Google,
"Cod war" Iceland fishery nursery
http://www.google.com.au/search?hl=en&q=%22Cod+war%22+Iceland+fishery+nursery&bt...

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"....And he said unto him, If they hear not Moses and the prophets, neither will they be persuaded, though one rose from the dead."
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freediver

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Re: Marine Parks as a Fisheries Management Tool
Reply #263 - Feb 26^th, 2009 at 10:21am

As for the alleged socio-economic impact, there is a tendency for some opposition before a marine park goes in. Afterwards, support for it tends to grow among fishermen as they see their catches improve. The only people who remain opposed are the extremists who would be ideologically opposed to marine parks regardless of the facts, because they think they have a right to fish wherever they want to. That is the extent of the socio-econonmic impact of a well implemented marine park network.

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pjb05

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Re: Marine Parks as a Fisheries Management Tool
Reply #264 - Feb 26^th, 2009 at 10:43am

freediver wrote on Feb 26^th, 2009 at 10:21am:

As for the alleged socio-economic impact, there is a tendency for some opposition before a marine park goes in. Afterwards, support for it tends to grow among fishermen as they see their catches improve. The only people who remain opposed are the extremists who would be ideologically opposed to marine parks regardless of the facts, because they think they have a right to fish wherever they want to. That is the extent of the socio-econonmic impact of a well implemented marine park network.

Well we musn't have any well implemented marine park networks in Australia then! The GBRMP has been a socio-economic disaster. At least those affected are being given compensation (unlike in NSW). The MP Authority, like FD downplayed the fallout. Compensation has now run to over 300 million - over a hundred times what the MP Authority said it would! No sign of improved fishing or a spillover effect. Quite the opposite actually. The few reefs still open near towns on the Southern GBR are feeling the effects of unprecedented fishing pressure.

FD you keep talking about facts when you dont have any. The way you studiously avoid the points I have made in my recent posts shows how little justification you have for your policy.

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pjb05

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Re: Marine Parks as a Fisheries Management Tool
Reply #265 - Feb 26^th, 2009 at 1:18pm

[600640]pjb05 wrote on Feb 24^th, 2009 at 2:37pm:

They (marine sanctuaries) would never have got this far if they weren't a superficially appealing idea.

Yup!

I admit it, this idea does sound superficially appealing to me.
But i also admit, i'm coming at this from the standpoint of a non-expert, and as a person without an 'interest' to defend.

It does seem logical, that in no-take areas [marine reserves] that are not subject to fishing, a natural, and a stable population of 'base' breeding stock population of fish would result?

If this is occurred, wouldn't this circumstance be a good thing?

Have a look a 'Burdens of Proof' - the benifits you describe are largely theoretical and could well be invalidated by a variety of processes.

I also understand [i remember this from a TV doco] that some species of fish need to attain a certain age / size before they start to breed.

With a practical need to protect a breeding stock population in all fisheries, surely such no-take areas [marine reserves] would be a very natural way, to help to facilitate the continuation of stable 'base' breeding stock populations, of many fish species?

Any sustantial fishing effort will involve the taking of adult (breeding fish). However you only need 30-40% of the spawning stock to be remaining to replenish the population and keep the fishery sustainable (termed maximum sutainable yield or MSY). At this level recruit classes benifit from less competion for food and less predation. You will actually get more out of the fishery if the larger fish are fished down somewhat. There is a price for having lots of large fish around - they eat lots of smaller fish!

Alternatively, if we [in Australia] decided to manage 'open' fisheries, which are always under [fishing] pressure, and [as a management strategy] we continue to take out the largest fish [i.e. much of the breeding stock population], is that smart, or is that dumb?

Refer to the explanation of MSY. Also even with a network of reserves they will always be under some pressure as most of them are highly mobile and their larvae is also mobile. They can be caught when they move outside the reserve. In any case even without marine reserves our fishery is not 'open'. There are non reserve forms of area managment such as large area bans on trawling put in place by fisheries departments. Marine reserves are a form of input reduction, ie they limit the ability of fishermen to catch fish. We already have many alternative forms of input reduction in the form of gear limits, trip limits, closed seasons and limits on the number of fishing licenses.

Quote:

However if the idea is to sutainable use the marine resource then the jury is out as to whether they are any better than traditional methods of quotas, limits on the no of commercial licenses, trip limits, closed season etc. If you look at the field evidence then the countries with the most sustainable fisheries have got there by relying on the latter - not marine sanctuaries.

pjb,

I'm coming to this topic as layman.

I admit, i have no deep knowledge of fishing regulations in Australia, and how effective they are [have been?], in protecting local fisheries.

Australia has the most regulated and therefore the least fished waters in the world. With the 3rd largest EEZ we import 70% of our seafood. The Commonwealth Fleet has been reduced from 1200 to just 600 boats. in NSW waters the no. of commercial fishermen has been reduced from over 7000 to a little over 1000 today. The GBR is fished at a rate of 100th of what is regarded as sustainable for coral reefs. The few remaining problems of overfishing can be dealt with by other means than locking up vast areas of ocean.

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pjb05

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Re: Marine Parks as a Fisheries Management Tool
Reply #266 - Feb 26^th, 2009 at 3:01pm

Quote:

Then there are all the problems with marine reserves. There is a huge socio-economic fall out on coastal towns affected by them.

Hey, 'Life's a bitch.' when someone is standing between you, and making a dollar. Wink

But i think that we can both agree that a 'huge socio-economic fall out' [for ourselves] is no good reason to rule out a fisheries management system which could help fisheries to be more sustainable?

Yes but the point is that you can make our fisheries more sustainable without the huge socio-economic fall out of marine reserves. Ie more of the same that got our fishery on a sustainable footing, eg reduction in commercial licenses, trip limits, gear limits, milder forms of area management, closed seasons, size limits etc. It must be remembered however that any substantial fishing effort does have an impact, but if you have any concern for humanity then what else can we do? It takes pressure off fish imports from more heavily fished waters than our own (which has to be paid for by other economic activity with its own environmental impacts). It takes some pressure of other methods of food production. Health authorities are constantly urging us to eat more seafood.

After all, any un-sustainable fishing practices [in any particular area] would also mean, 'a huge socio-economic fall out on coastal towns',
....when a fishery collapses due to over fishing [which has happened, in some northern hemisphere fisheries]?

But its not happening here and it's not likely to either. We don't know what the full effects are of marine reserves, so if you take the precautionary principle far enough, even they fall foul of it!

But i do agree, that a fisheries management system which equates with 'best practice' should be sought out / determined on the evidence.

Quote:

The angling experience is degraded by the loss of most of the good fishing spots, overcrowing of those remaining, difficulty in complying (trying to keep track of lines drawn in the water), heavy fines or worse for usually innocent errors.

Most ppl have access to GPS technology today - so why don't they know that they are fishing [from a boat] within a 'posted' marine sanctuary?

Not everyone with a small boat has a GPS. Few would have a GPS chart plotter (ie one with a map), which is the only type of use determining if you are in a green zone. Even then you will need a map insert showing the green zones and these aren't available for all marine parks!

Allow a warning to be issued, for a 1st offence, with a 'cancelled' fine?

And on a 2nd offence [within 6 months], issue fines for both the 2nd & the 1st offence?

That would be too lenient it would seem for our marine park authorities. On the GBR 320 anglers got criminal convictions for fishing in green zones (usually accidently and first offence). The conviction rate is 99%. Our NSW marine park rangers (fun police) have been shown the be on the overzealous side also and unlikely to give up a scalp. All this points to an anti fishing bias with the whole concept.

Quote:

People have bought houses by the beach with the idea of throwing a line only to have fishing banned there when a marine park was declared!

That is hard [....the after the fact declaration of a marine park].

It could alleviate a lot of these problems [for existing residents] if authorities tried [where possible] to limit declaration of marine parks to offshore, and uninhabited shoreline areas?

Is that suggestion realistic?

There is a tendency to close down fishing spots merely because they are poupular fishing spots. Also they want a represenative area of each habitat as a green zone so that incudes beaches. It is extremely doubtful that a green zone on an ocean beach will have any benifits for the fishery as a whole.

Would it be possible to allow, within a marine park, shore based line fishing [having only a very localised, minimal impact?], but no boat fishing [and no spear fishing]?

See above - they want representative areas. Also why single out boat fishermen? A lot of shore based spots are dangerous, hard to access or already overcrowded. People who are less mobile will be singled out by stopping them fishing from boats. There are safety implications pushing people to fish off ocean rocks.

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Re: Marine Parks as a Fisheries Management Tool
Reply #267 - Feb 26^th, 2009 at 3:26pm

[quote author=Yadda link=1192441509/255#262 date=1235600640

Fighting cod war taught Icelanders the lesson of conservation
16 August 2000
.....For Britain the issue was jobs on Humberside, but for Iceland it was national survival. Before anyone else, islanders realised what a terrible problem overfishing would cause.
.....The science of limiting fish catches so as to maintain renewable resources for future fishermen was, to start with, poorly developed.
.....And, as in the European Union, which also claims to manage its resources, there is always political pressure to allow extra catches.....
.....Nearly 25 years on, Iceland is seen as a shining example of how stocks can be managed, even though the system is still not perfect. Each vessel carries its own quota of fish, catches must be carefully logged, and it is a matter of pride to stick to the rules, knowing thereby that fishermen are providing for their own future.
There are extensive nursery areas that are permanently closed to fishing.
.....In the North Sea, because there are no safe havens, few fish of spawning age are spared, hence the parlous state of stocks. Some believe cod will disappear altogether.
.....The answer is to take a lesson from Iceland and control stocks on a strictly scientific basis with proper zonal management.

http://www.guardian.co.uk/environment/2000/aug/16/fish.food1

Google,
[b]"Cod war" Iceland fish

I think you will find that Iceland got where they are without relying on marine reserves as the main management tool (even thought they may have a few). They relied on traditional restrictions worked out by their Fisheries Scientists, as did countries such as Australia, NZ and the USA.

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Yadda Gold Member Offline Posts: 21956 A cat with a view	Re: Marine Parks as a Fisheries Management Tool Reply #268 - Feb 26^th, 2009 at 6:39pm pjb, As i said, i have no expertise [and no real or personal interest, atm] in this area [fishing]. Thanks for your reply to my post / queries.
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pjb05 Gold Member Offline OzPolitic Posts: 1403 Gender:	Re: Marine Parks as a Fisheries Management Tool Reply #269 - Feb 26^th, 2009 at 6:44pm Yadda wrote on Feb 26^th, 2009 at 6:39pm: pjb, As i said, i have no expertise [and no real or personal interest, atm] in this area [fishing]. Thanks for your reply to my post / queries. No worries, Yadda. Now where has FD got to?
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