Önemli Verilerin Eksikliğinde Kararlılık Analizinin Sürdürülebilir Balıkçılıktaki Önemi

Year 2023, Volume: 19 Issue: 1, 71 - 87, 01.03.2023

Mahir Demir

https://doi.org/10.22392/actaquatr.1179986

Abstract

Aşırı avcılığın önlenmesi ve sürdürülebilir balıkçılık politikalarının elde edilmesi için balık stoklarının yönetimi çok önemlidir ve balık stoklarını analiz etmek için XSA, VPA, BMS, CMSY ve MSVPA gibi birçok stok yönetim metotları vardır. Fakat bu stok yönetim metotlarını kullanmak için balık stoklarının beslenme verisi, doğal ölüm oranı, avlanan balık miktarı, balık stoku miktarı indeksi, avcı balık oranı gibi önemli dataların olması gerekir. Ne yazık ki, birçok balık stoku için bu tarz verilere sahip değiliz ve bu verileri elde etmek ekonomik olarak çok maliyetli ve zaman alıcı. Fakat bu veriler elimizde olmasa da matematiksel modeller ve kararlılık analizi yardımıyla balık stoku miktarı, maksimum sürdürülebilir avlanma miktarı, av-avcı ilişkisinin balık miktarına etkisi, avcılığın türler arası av-avcı ilişkisi üzerine etkisi gibi balık stokları ile alakalı birçok önemli bilgiye ulaşabiliriz. Bu önemli model çıktılarını elde edebilmemiz için, sadece avlanan balık miktarı verisi ve oluşturulan matematiksel modelin kararlılık analizine bağlı parametre tahmini yapmak yeterlidir. Kısacası bu çalışma, balık popülasyonları ile alakalı önemli veriler elimizde olmadığında, kararlılık analizinin balık popülasyonları ile alakalı önemli bilgileri elde etmedeki öneminden bahsetmektedir.

Keywords

Besin zinciri, Av-avcı ilişkisi, Denge noktası, Kararlılık analizi, Sürdürülebilir balıkçılık

Importance of Stability Analysis for Sustainable Fisheries in the Absence of Important Data

Abstract

Assessment of fish stocks is especially important to avoid overfishing and obtain sustainable fishing policies, and there are many stock assessment methods such as XSA, VPA, BMS, CMSY, and MSVPA to analyze fish stocks. However, these assessment methods require an important amount of data for fish stocks such as diet data, natural mortality, fishing mortality, abundance index of species, predator ratio estimates, and so on. Unfortunately, we do not have such data for most of the fish stocks, and obtaining such data requires an important amount of money and time, but we still can predict important information about fish stocks such as biomass of fish stocks, the maximum sustainable yield, the biomass of fish lost or gained due to predator-prey relations, and even can track the effect of harvesting on predator-prey relations by building a mathematical model for fish populations and implementing a stability analysis. To obtain these outputs, we only need landing data and implement a parameter estimation constrained on stability conditions derived from the stability analysis of the mathematical model. Shortly, this study shows us how important stability analysis is to obtain important information about fish populations in the absence of important data.

Keywords

Food chain, Predator-prey relation, Equilibrium, Stability, Sustainable fishery

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