Showing posts with label Washington State Department of Fish and Wildlife. Show all posts
Showing posts with label Washington State Department of Fish and Wildlife. Show all posts

Thursday, July 1, 2010

Plugging a Leak



The Puget Sound Salt Water Tide Pool at Pacific Science Center is in great shape for an exhibit of over twenty years. But after a year of close calls and “band aid” fixes, we realized that the time had come for some major plumbing repairs. PVC becomes brittle with age, and there were signs that some of our pipes would not last much longer. While many home owners can tell you that any sort of plumbing repairs can be tricky and burdensome, in this instance there was a special catch. Plumbing cannot be repaired with water in it. And if the water was gone, the animals had to go too.



Enter the Seattle Aquarium, whose Curator of Fish and Invertebrates, Tim Carpenter, generously offered to accommodate the animals while we got our plumbing work done. Washington State Department of Fish and Wildlife was equally helpful in providing us with all the permits we needed to transfer the animals off site. No wildlife should every be captured or transported without a clear purpose and without first completing all necessary permitting.

Having secured a place for them, we had to remove the animals from their home, which they had become quite attached to. Literally. Sea stars and sea urchins cling to the stony shores with many tiny tube feet. Anemones hold on with a single, powerful base that adheres tightly to rocks. Chitons and limpets can attach so firmly that hungry gulls can’t pry them from their stones. And while fishes don’t stick to things, they are very good at hiding. Only the hermit crabs are actually easy to collect.

But through patience and gentle prying, we were able to collect our animals and sort them by group into buckets. Predators like sea stars and anemones were kept separate from their food items, such as hermit crabs and shell fish.

While the animals were away, there was more to do than plumbing. We changed out all the sand and water, cleaned the filter medium and changed the manifolds. We had a good deal of help from PSC staffers in other departments who were excited to help our tide pool animals. Various staff members from IT supervisors to cashier coordinators, helped us empty and clean the tide pool, and transport our animals safely to and from the Aquarium.

The animals appear to have done well while they were away, and we are grateful to the aquarium for all of their help. But we were eager to have them back in our tide pool. We wanted them to stay in good condition upon their return, so before they went back in we tested the water’s salinity, temperature and pH. Although marine life amazes us with its ability to survive difficult conditions, the better care it gets, the more likely it is to do well.

Even with the best care, we expect the first week they are back to be rough. Though the water is sparkling, we are keeping the exhibit closed until we are certain that the anemones have formed good strong bonds with the substrate. We will be excited to reopen the exhibit and we’re sure there are also plenty of visitors out there who will be excited to see, touch and learn from these fascinating creatures again!

Read more!

Tuesday, March 9, 2010

Tide Pool Census 2009


Pacific Science Center’s Puget Sound Saltwater Tide Pool is home to animals collected under a Scientific Collection permit, issued by the Washington State Department of Fish and Wildlife (WSDFW). Without a permit, it is illegal to gather animals from beaches. With a permit, it is still Pacific Science Center’s responsibility to take animals correctly, gathering only what will be used and leaving the environment as intact as possible.



Each year we submit a list of all the animals we have collected in the last 12 months. In addition to being a requirement, this is a tool for us to assess how well different species do in the exhibit.

Below is a list of the animals collected in 2009 and the census of animals present at year’s end. This is a shorter version of the list we give the WSDFW, which gives details to genus or species level.



In some cases, there are more animals listed than we collected in 2009. The extras are animals collected in previous years – a sign that they are doing well in husbandry for that group.


Other animals are collected in substantial numbers and yet none are present at year’s end. In the case of shellfish, this is planned. Clams, barnacles and mussels are collected as food items for the sea stars. In other cases, such as “small assorted animals” we may still have the animals but cannot find them. Isopods, tiny anemones and small shrimp routinely work their way into our filter beds, where they live free from predators, and well nourished by the remnants of food left by other animals.



In some cases, though, the species is simply not doing well in our environment. Sand dollars, for example, have very specific habitat needs that are not met in our enclosure. This is an animal we are unlikely to collect in the future.


We had a very marked change in survival rates for anemones, urchins, and sea stars when we installed a hand rinse sink in 2003. Previously these animals could not be touched without rapid loss of health. Now they are highly resilient to touching. Contaminants on people’s hands were more harmful than the physical fact of being touched.


Hermit crabs are a special case because guests are allowed to handle them. Sadly, they did not experience the same jump in survival rates when we got the sink, and we are still working on ways to increase their longevity. The biggest risks to our hermit crabs seem to be, in order from highest to lowest: wandering into unsafe areas, fighting with each other, and rough handling by people. One way we have found to keep them healthy is to keep the population relatively low. An enclosure with twelve to 15 hermit crabs will remain stable, but one with twenty or more will experience losses until the number drops below 15.


Keeping these statistics is the best way for Animal Caretakers to track and assess our tidepool husbandry procedures.

-Sarah Moore, Life Sciences Manager

Read more!