The Benthos Bares All

We are familiar with the many wonderful animals and birds that rely on the glistening streams and ponds which wind their way throughout Baltimore Woods. But some may not be familiar with the beautiful and amazing invertebrates that inhabit those same waters. As of late the woods have been bustling with the excitement of parties and school groups as they flood the woods for our stream and pond ecology programs. With all these busy little hands and feet dipping into the water and discovering these amazing creatures I thought it time to give them their spot to shine.

Aside from being amazing to look at these invertebrates play an immense role in the ecology of a stream and can be a key indicator species, meaning a species that can detect shifts in the environment. Specifically scientists have found that looking at the benthic invertebrates can be most telling. By simply looking at the types and variety of species present you can inference the water quality in an area and the health of an ecosystem! Amazing! But don't just take my word for it, let's explore some of the science:

Water Quality

These benthic macro (meaning large enough to see without a microscope) invertebrates survive in different conditions. For example some are very sensitive to poor water quality while others don't mind it. Various things, besides chemical pollution, can alter water quality; warm water temperature, murky sediment filled waters, and low oxygen levels can also lead to poor water quality and sensitive species can't survive. Therefore the types of invertebrates you find at a location can tell you about the water quality! The presence of sensitive species indicates high water quality and the absence of these species indicates poor water quality.  

Ecosystem Health

Biodiversity, or the number and variety of different species present in a particular area, is often used as an indicator for the stability of an ecosystem. This is because the more diversity present, the more likely an ecosystem can recover from a catastrophe (like a disease or plague), making it a more stable ecosystem. Many scientists correlate this stability with the "health" of an ecosystem. Hence, the more variety you see in the macro benthic invertebrates the healthier the ecosystem! 

How crazy is that! Who would think that having fun with these amazing crawly critters could tell you so much about the habitat? Now, while there are many stars to this show, below are some of my personal favorites out of the bunch.

 Stoneflies

This is a sensitive group of macroinvertebrates, which means it is pollution intolerant. We found a ton of these in Baltimore Brook at the bottom of the Valley Trail. They're a great indicator of clean, cold, healthy water like those that flow from our springs. Mayflies are easily mistaken for this little guy, who looks very similar but with the addition of a third tail and the fluttering gills along the abdomen.  

Caddisflies

I love to look at the amazing cases that these guys can make. They can be made out of pebbles, sticks, or whatever substrate is in the area. Some people even grow them in substrates containing gold and jewels and make jewelry!

Dragonfly larvae and leeches
These tolerant species were found in one of the murky ponds just off the lower parking lot, they indicated low water quality. The neat thing is that there was still a high diversity of them, we saw 3 different species of leeches. This indicates low water quality, but a healthy ecosystem.

So next time you're wondering the trails and you see a party of people wading through the streams with dip nets and poking through pails of water you'll know just what they're up to. Not only are they having some fun splashing around, but they're helping Baltimore Woods check-up on its water quality and biodiversity.