Earth Day Thoughts: Three Ways You Can Help Seahorses
Earth Day is meant as a reminder of what we can do as individuals to help the environment. I thought I’d use this Earth Day to spread the word about seahorse conservation. Specifically, some actions every individual can take to help impact the survival of seahorses. Here are three threats to seahorses, and actions every one of us can take.
Limit Shrimp Consumption and Choose Wisely
Shrimp is delicious. But did you know shrimp trawling is extremely harmful to seahorses? The majority of all seahorses fished from the ocean come as a by-catch, and a significant percentage is from shrimp trawling specifically. Seahorse and shrimp occupy the same habitat, so when you catch one, you’re bound to catch the other.
In general, shrimp trawling is extremely damaging to the ocean’s ecosystem. It tears up the bottom and leaves rubble in it’s wake. It creates silt plumes which can cover and smother nearby reefs. And it indiscriminately catches other sea life. For every pound of shrimp, up to 20 pounds of discarded sea life is caught.
What can you do about that? It’s tough, it’s a big problem for seahorses. But shrimp fisheries aren’t going anywhere. Farmed shrimp seem like the ideal alternative, but much shrimp farming is damaging to the environment around it. Recirculating and inland systems tend to be the least damaging.
Reduce Your Carbon Footprint
By now, you’ve probably heard the necessity of reducing your “carbon footprint”. The production of CO2 impacts so many aspects of the Earth’s ecosystem that the list almost becomes mind-numbing. But it is so important. If the other reasons don’t spur you into action, do it for the seahorses.
Seahorses are vulnerable to excess CO2 by two important mechanisms. Warming oceans threaten the existence of seahorses, and ocean acidification from increased CO2.
Ocean Acidification is less talked about than global warming and increased ocean temperatures, but it also threatens sea life, and seahorses in particular. CO2 dissolves into the oceans water and creates carbonic acid. This acidification threatens sea life that is dependent on calcium for growth, such as corals. But often forgotten is this has the potential to affect seahorses more than other fish. They have a bony exoskeleton, putting them at a higher risk than other fish species.
We know that sea life is negatively impacted by ocean acidification from CO2, because it happened before. The Permian-Triassic Extinction Event lead to the death of 96% of marine life. This was due to massive amounts of CO2 in the atmosphere, the reasons for which are still debated. The most hard hit marine life was invertebrates which relied heavily on calcium structures. And while seahorses are fish, not invertebrates, it stands to reason that they would suffer the same fate due to their bony armor.
While the specific risk to seahorses is just hypothetical, we know corals are at risk from acidification. While many seahorse species rely on seagrass beds, there are a number that prefer coral reefs. If coral reefs collapse due to ocean acidification, so do those seahorses.
Unfortunately, there is lots of evidence we’re quickly heading to the same level of CO2 that caused the Permian-Triassic Extinction Event.
Increased ocean temperature is another problem seahorses face. The Canary Islands have been invaded by tropical species due to warmer ocean temperatures. During a survey of seahorses around the island in 2008 and 2009, something surprising was found. The tropical seahorse Hippocampus algiricus was found to have invaded and two pregnant males had crossed with the native species .
This was the first evidence of naturally occurring seahorse hybrids. It’s suggestive of the damage that can be done to a species when a new one invades territory inhabited by different species. Cool water species may be breed out, out competed by seahorses with more temperature tolerance, or hybridize to become a new species; we simply don’t know.
Seahorses are also particularly vulnerable to bacterial disease, and one they are most susceptible to thrives at warmer temperatures. It has generally not been a significant problem in wild seahorses but could become one with increased temperature.
Temperature also plays a part in the amount of oxygen water can hold. Seahorses have unusual gills that look like grape clusters. Unfortunately, they’re less efficient at respiration than other fish. Warmer temperatures and reduced dissolved oxygen will be problematic for all fish species, but more so to the sensitive seahorse
Mashable offers some practical tips on reducing your carbon footprint. CarbonFund.org has an exhaustive list of steps to reduce your footprint, along with offering carbon reduction programs to offset your carbon use.
Litter and Trash Cleanup!
This one is a favorite of mine, and one I want to encourage as many people as possible to do because it’s something that each person that participates in this activity can have a visible impact. Clean up any trash or garbage you see. Especially near bodies of water. If you don’t live near the ocean, don’t let that stop you! Studies have shown that plastic debris makes it way from great distances to the ocean via wind, storm drains, streams and rivers.
I’m cheating here. There was very scant research on the effect of marine debris and seahorses. However, trash impacts sea life on so many different levels that it’s hard to imagine it wouldn’t impact seahorses.
Fishing line is particularly deadly. If you’re a fisherman, clean up fishing line. I’m astonished at the amount of fishing line that is often left on shore, tangled in brush, or just a few feet into the water. If you see fishing line, remove it and discard properly in a waste receptacle. Anglers should consider switching to biodegradable fish line to reduce the damage from line lost in the water.
One of my favorite ways of “giving back” to the environment is doing litter cleanups while on vacation. If I’m near the ocean, I try and take some time (sometimes a day, sometimes an hour, sometimes a single garbage bag). It’s a small thing to do but every piece helps. Even just grabbing obvious trash when sight-seeing can help. I often imagine if every tourist did this small step, what a difference it would make. It goes without saying, be aware of your trash, especially when traveling. Tourists are well known for excessive litter.
Want to do more? There are also local and national waterway cleanups. The Ocean Conservancy organizes an annual event to clean up along the worlds coasts and offers advice on organizing a local cleanup event.
Interested in learning more about seahorse conservation? Take a look at our conservation articles.