Climate change brings two irreversible risks to marine life i.e. rising water temperatures and acidification of the oceans The ocean absorbs greenhouse gases like carbon dioxide (CO2) and heat from the atmosphere.
As the ocean absorbs more CO2 from the atmosphere, a sequence of chemical reactions occurs, causing its pH to drop, making it more acidic. This reduces the amount of carbonate ions that are available, which are needed by different types of fishes to help form their skeletons.
These underwater creatures form the foundation of marine life, and a decline in their numbers could destroy the marine food chain. While fish do not have shells, a minor rise in acidity can induce acidosis, irregular development, and internal chemistry problems. Fish living in rivers, streams, lakes, and other freshwater ecosystems can also be affected by pH imbalances caused by acid rain.
What Effects Will Climate Change Have On Fish?
Every animal, including fish, has an ideal temperature range and set of conditions. While certain aquatic creatures can easily adapt to rising temperatures, others may become stressed or even die.
1. Stress Response In Fish
In stressful environments, fishes like Mahseer, King fish and Rohu fish show various kinds of survival responses. Their responses include adaptation, migration, death, or just bearing with the stress. Numerous fish species have already been observed to employ such strategies. Researchers have seen winter skates, for example, change their body size to survive in warmer seas.
Similarly, in response to changing climates, the summer flounder, an economically significant species, has moved its range around 70 miles northward throughout the 1970s.
2. Decreased Fish Stock
However, some consequences of climate change are harder to detect than others, such as expanding ranges or declines in fish populations.
Fish stock productivity, or the overall number of fish that are born and reach adulthood in a population, can be negatively impacted by stress brought on by a changing ocean. Decreased productivity has the potential to impact the ecosystem and reduce the amount of fish that are produced.
3. Threats To Fish Habitats
Predicting fish’s reaction to climate change requires more than just considering their temperature sensitivity. Even if a species of fish can adapt to warmer waters, other effects of climate change, such as heatwaves, algae blooms, and storms, can severely damage the ecosystems on which the species depends. If fish do not have food or a place to reside, there comes a habitat problem.
What Should We Do To Reduce The Negative Impact Of Climate On Fish In Pakistan?
The fish export and import in Pakistan encounter severe challenges as a result of climate change. Several methods can be used to reduce these negative effects and guarantee the sustainability of fish populations:
1. Prioritize Greenhouse Gas Reduction
Our top priority must be to keep lowering greenhouse gas emissions. There are some ocean-based climate solutions that are both feasible and effective. However, even if we are successful in lowering the level of greenhouse gas, we know that global warming will still cause significant problems for fish and fisheries. Therefore, we must adjust fisheries to the changing climate.
2. Build Climate-ready Fisheries
To prepare our fisheries for climate change and maintain sustainable fish populations, we require more research on how fish adapt to current conditions to assist us predict how they will behave in the future. This includes planning to increase the number of fisheries surveys, integrating traditional ecological knowledge into science and management, and funding impact research.
We can’t act until we have perfect knowledge. Fishery management can take proactive measures to ensure that fishermen and fishing communities can adapt, as well as activities to boost fish stocks to make them more robust to climate change.
3. Climate Vulnerability Assessment
Many of the work described above has already begun, but there is still more to be done. You can use the Climate Vulnerability Assessment Tool, which was recently launched by NOAA Fisheries, to see how vulnerable fish and marine species are throughout the country.
The NOAA Distribution Mapping and Analysis Portal also allows you to track historical changes in fisheries ranges, which can provide useful insights into how fish populations adapt to environmental changes.
Conclusion
Climate change brings major challenges to fish in Pakistan, including rising water temperatures and ocean acidification. These changes may disturb fish populations and habitats, affecting their survival and productivity. In order to mitigate these effects, efforts should be made to reduce greenhouse gas emissions, promote sustainable fishing techniques, and expand research on fish responses to climate change. Collaboration and proactive actions are critical to ensuring the future of fisheries in Pakistan.
