Friday, March 3, 2017

Eyes Under Puget Sound: The voucher sheet project

The first page of a voucher sheet
for Lucinoma annulata.
This month, we’re taking a break from our regularly scheduled Critter post to tell you about an exciting venture we’ve been working on here in the benthic lab: the voucher sheet project.


Since 1989, our Marine Sediment Monitoring team has collected over 1,200 different types of sediment-dwelling invertebrates (also known as the benthos) from Puget Sound. As the team’s taxonomists, it is our job to put a name to each little face! We use several methods to be sure we have the names right, one of which is referencing voucher sheets. A voucher sheet is a short document that contains descriptions and photos of each species.

Sort it out

LEFT: A jar of marine worms gets emptied into a dish to
await identification. MIDDLE: In the process of morphotyping.
RIGHT: The completed sample, identified and labeled by species.
It all starts when we sit down at our microscopes and open up jars containing hundreds of tiny preserved animals from our monitoring work in Puget Sound. Each jar gets dumped into a dish, and the animals are “morphotyped” – sorted into piles of similar-looking species based on their physical characteristics. Some species are distinct, and we recognize them right away. Others require delving into books, journals, online references and any other bits of information we can find in order to unravel the mystery of their identities.

A completed voucher sheet for the ostracod Euphilomedes carcharodonta.


Detective work

Searching for taxonomic literature takes a LOT of time, and many references don’t contain illustrations. We’ve set out to help solve this problem by creating a set of Ecology publications called Benthic Invertebrate Voucher Sheets. It’s a large undertaking – we’ve completed 50 and have many more in the works!

A close-up of the feet of the marine worm
Cheilonereis cyclurus shows the tiny hairs
and other features that make it distinct.

What's in a voucher sheet, exactly?

After we do our review of the literature, we create a voucher sheet that includes a basic classification, a general description and most importantly, a list of diagnostic characteristics which set that species apart from other similar-looking species. Using cameras attached to our microscopes, we take photographs of these diagnostic characteristics, even features as teeny as the hairs on a worm’s foot! These high-quality images illustrate exactly what to look for when we examine a specimen.

Benefits for Puget Sound and beyond

By generating accurate data on what species are present in our samples, we can detect changes in the benthos over time as they respond to environmental stressors like those associated with climate change and pollution.

Dany uses a microscope and attached camera to
take a photo of a marine worm in the family Ampharetidae.
Voucher sheets not only help us correctly identify the critters we monitor, but they will also help other scientists doing similar work. Most species we collect aren’t limited to our region - many can be found all the way from Alaska to Mexico.

Scientists working in other regions can access our voucher sheets to help them correctly identify the invertebrates they collect. This is one way to improve taxonomic standardization – that is, making sure animals are identified the same way by taxonomists working in different areas – and expand the body of knowledge about our valuable biological resources.

By: Dany Burgess & Angela Eagleston, Environmental Assessment Program

Critter of the Month

Our benthic taxonomists, Dany and Angela, are scientists who identify and count the benthic (sediment-dwelling) organisms in our samples as part of our Marine Sediment Monitoring Program. We are tracking the numbers and types of species we see in order to understand the health of Puget Sound and to detect any changes over time.

Dany and Angela share their discoveries by bringing us a benthic Critter of the Month. These posts will give you a peek into the life of Puget Sound’s least-known inhabitants. We’ll share details on identification, habitat, life history, and the role each critter plays in the sediment community. Can't get enough benthos? See photos from our Eyes Under Puget Sound collection on Flickr.

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