Let’s talk about the beautiful Gulf of California, which exists in all of its beauty because of the flow of freshwater from the Colorado River. A flow that is reaching the Gulf less and less nowadays. You see, since the damming of the Colorado River the amount of water that reaches the mouth of the river in Mexico has dropped, and in certain years no water reaches the mouth. That’s a problem.
The Gulf of California is important for a number of reasons. For 891 fish, 181 bird, 34 marine mammal, and seven marine reptile species this is where they live, reproduce, and feed making this one of the Western Hemisphere’s most diverse seas. Because of this it is also where over 60% of the fish and 90% of the shrimp caught by Mexico are taken in, but the number of fish caught every year is dwindling (this can also be attributed, in part, to overfishing). The Gulf is also very important to Mexico’s tourism industry with people going there to sport fish, scuba dive, and relax on the beautiful beaches. But all of this beauty and diversity is at risk because of what is going on upstream in the US.
So what’s going on upstream? Dams. Dams hold back the two things that the Gulf needs to survive; water and sediment. Historically, the Colorado River deposited
between 77 and 91 million tons of sediment into the Gulf every year. This sediment is the nourishment that is needed by plants and small animals to survive. But today most of the sediment is caught behind the walls of the Hoover Dam and the Glen Canyon Dam, never making it anywhere near the Gulf.
The waters of the Colorado River are also held back by the dams. This by itself reduces the flow, but there are other factors such as evaporation of the lakes formed behind the dams that also lead to reduced flow. A report by the US Bureau of Reclamation says that the loss from evaporation alone is over 15%.
The fact that water isn’t reaching the Gulf leads to another problem: salinity. If the system was working correctly the northern part of the Gulf would be less saline than the southern part due to the freshwater flowing in from the Colorado, but it’s not. Saline water has negatively impacted the habitats of many plant and animal species that thrived here for centuries while the flow was natural. Also, the salinity of the lower Colorado River is changing due to lack of flow. In its natural state the lower Colorado river had a salt content of 50 ppm, but by 1960 that had shot up to over 2,000 ppm. This is causing millions of dollars in damage to crops that use this water, both in the US and in Mexico.
While there’s little that can be done upstream short of taking down the dams (which won’t happen) conservation efforts in the Gulf have been steadily increasing in recent years by organizations such as The Nature Conservatory and the World Wildlife Fund, but they’ve been faced with challenges. One is that the fishing industry doesn’t want to lose any money, and they fear conservation means they’ll be able to catch less. Conservation groups realize this and try to come up with economically viable solutions, but most of the time these solutions are still defeated by the fishing industry. What the industry doesn’t understand, or isn’t thinking about, is that if they don’t do something now they won’t have any fish to catch at all.
Another problem that the Mexican government faces is how to enforce laws that are put into place to help with conservation. The coastline of the gulf is thousands of miles long, and it takes a lot of resources to monitor the area, and enforce any laws that are broken. Also, the Mexican government isn’t at a consensus as to how important conservation of this area is, and so conservation laws are often not passed. This doesn’t make any sense especially since the Mexican government and businesses want to develop the gulf as a tourist destination (something that I’m sure will also have negative impacts on the environment).
So what happens now? Well, that’s a good question that I don’t have an answer to. The dams are staying, and as the climate warms I would bet that the amount of water released isn’t going up. People have thrown out ideas of using treated water from treatment plants to increase the flow of the river, but that idea hasn’t gained much ground because of a legitimate fear of what will still be in the treated water. Our best hope is that conservationist can gain ground with the people, government, and industry in Mexico and make some positive impact. But with the water becoming more and more saline I don’t know how much conservation is going to do. If the plants and animals can’t survive in the region because it’s too salty what are you conserving?