Wednesday, September 18, 2013
synthetic salt mixture. This gives us a more consistent product unaffected by rain, pollution, etc. However, we are at the mercy of our equipment. If our hand rinsing sink failed, and kids touched our water with soapy or lotion covered hands, we would notice an immediate decline in the health of our animals. When our protein skimmer goes on the fritz, we quickly lose water quality.
Although Seattle’s weather is mild, fluctuating from occasional 90° days to weeks of freezing weather in winter, the water temperature of Puget Sound ranges from a low of 6.7° C (44° F) in winter to a high of 13.3° C (56° F) in summer. We maintain the water in our tide pool within this range of temperatures.
But the good old chiller is supposed to take it back down to the colder end of things overnight so it’s ready to go again the next day. Without its help, the water would eventually rise to room temperature!
Of course, the longer-term impact of warmer water wouldn’t be as positive for the animals. Warmer water holds less dissolved oxygen and more algae growth. If too much algae flourishes, its decomposition strips yet more oxygen from the water and can lead to serious problems for the animals.
Lower oxygen levels harm the ability of animals to resist disease and pollution. So when waters warm, animals that appeared healthy may start succumbing to preexisting disease, or may develop problems from injuries that would normally be very minor. Animal’s behavior also changes as they seek more oxygenated water. In the wild, they might migrate to deeper water or to areas with pockets of trapped cold water, or populations might start trending further north. In the tide pool, animals would seek oxygen near the water’s surface, even though it was warmer. As normally deep-water creatures moved to the surface, competition for good spots would lead to more animals fighting and injuring each other.
Luckily for our tide pool, these problems did not have time to express themselves. Our chiller had a bad circuit.Once Douglas Hall, our electrician, replaced it, temperatures quickly returned to normal.
There is no such quick fix for the climate changes that are raising the temperatures in Puget Sound. But understanding the risks, from a mini-model such as our touch tank, can make it all the more clear why it’s important. Reducing carbon emission is the best way to slow the rise of sea temperature, but keeping beaches otherwise healthy and intact – free from polluting runoff or from overuse – is also critically important. Resilient animals will be best able to withstand, adapt, and survive in a rapidly changing environment. Intertidal life, with its tides, fresh water feed, and periodic predation by shore life, is by nature challenging. Human intervention should aim to minimize the added challenges we throw at these already hard working systems.
Posted by Terry at 6:07 PM