Little creek behind my house; stream morphology

[Shane]

This is a two part post. Firstly my 5 year old daughter and I did some collecting in the little stream behind the house we just purchased in Virginia. While collecting I also took some time to document some stream morphology, or microhabitats.

Catch was mainly Rhinichthys atratulus (Blacknose Dace), a single Rhinichthys cataractae (longnose dace) and four Lepomis cyanellus (Green sunfish). We kept some blacknose dace, the single longnose, and a mated pair of the sunfish and set them up in an antique 15 gallon tank (stainless steel frame, slate bottom). Old school tank, old school fishes.
-Shane

[Shane]

I am going to do each of these as a separate post as I have a heck of a time aligning lots of pictures and text in one post.

Many readers hear us talking about cutbanks, riffles, rootballs, undercuts, sandbars, etc when talking about collecting. I thought it would be useful to document some stream morphology. I also hope to give people some natural habitat inspiration when they aquascape.

The stream below is a piedmont, or hillstream, in Virginia, USA.

Habitat One: The Riffle. Riffles occur where the gradient (slope) of the land causes the water to move faster. As the water moves faster, sand and small stones are washed away by the current leaving a substrate of primarily larger stones. The current wears these rocks away over time leaving them well rounded without sharp edges.

In South America a riffle section would be home to Chaetostoma, some Ancistrus spp, some Hemiloricaria and various tetras and cichlids adapted to live in strong currents. In Africa the same habitat would be home to Chiloglanis.

[Shane]

The Cutbank: Where streams make a turn the flow of water, especially in the wet season, will erode the outside bank of the creek or river. This erosion often exposes roots from terrestrial plants and trees and these cutbanks can be surprisingly deep. They are a great hideout for predators as the current naturally brings prey towards them while the cave-like structures created under cutbanks provide homes and places to strike from.

Cutnbanks, in South America, will be home to pimelodids and pseudopimelodids as well as predatory cichlids and tetras. They can also be a home to large loricariinae and spp such as larger, well armored spp like Hypostomus and Cochliodon.

[Shane]

Exposed Bank: Here shallow cutbanks have exposed many roots from terrestrial plants and trees. Replicating this environment in the aquarium can be very attractive and rewarding. A shallow environment like this in South America would harbor many Farlowella and Otocinclus. The same cutbank in deeper waters would be a good location to collect Discus.

[Shane]

The Rootball: Here a tree has been knocked down by erosion. Its trunk and root structure create many hiding places. While these structures are very difficult to collect, they turn up loricariids, doradids, and auchenipterids in South America.

[Shane]

Typical stream bank. Note the exposed roots and stones as well as the overhanging terrestrial vegetation. This is a quite generic habitat that might house many different species. A good overall reference for a typical community type tank that is not really trying to model a specific microenvironment.
-Shane

[kruseman, posts: 275]

I do have such a nice daughter of the same age you have. I don't have such a lovely stream behind my house. Well,you can't have it all.

A very nice topic.

[MatsP]

A great read.

--
Mats

[bigbird, posts: 229]

wow may i say it is wonderful that your children have such a joy in this passion. My 2 also love the fish and tanks and now you have givem ,e another idea on how to get them more involved. thks jk

[Jools]

I must get the "thanks" feature working so people can rate this excellent thread!

Jools

[andregurov, posts: 101]

Nicely informative (with pics!) and delightful to read. Thanks for posting it up.

[NielsV, posts: 38]

Great pics, you live in a beautiful area!

[AleGer, posts: 448]

Shane thanks for this thread!:)

[Shovelnose, posts: 874]

Lovely thread Shane!!!!

[Suckermouth, posts: 1520]

Shane, did you keep track of where you found the Rhinichthys in those different types of stream microhabitats? My labmate is working on Rhinichthys, and I'm curious if their habitat choice was consistent with their choices in the midwest and the southeast where we've sampled so far.

[MChambers, posts: 70]

This is a great thread. Thanks for posting it.

I have great kids, but they are now teenagers and don't have much interest in the aquariums, although my daughter did reignite my interest in fishkeeping 6 or so years ago when she announced she wanted to breed guppies.

We don't have a stream in our backyard in DC, but a very fun thing to do with kids here is to visit Rock Creek when the herring are making their spawning run in the spring. Just south of the National Zoo, there's a spot where the herring pile up waiting to cross an old ford. There's also a ladder at Pierce Mill.

http://www.audubonnaturalist.org/default.asp?page=712

http://www.youtube.com/watch?v=aC6lSoUQsCo

[rhibear, posts: 34]

Lovely thread. I would love to know where in VA you are located. I am in Richmond and love to see what I can find in the James River with a pocket net and jam jar.

[Shane]

Firstly, I am very happy that so many people are enjoying this thread!

Shane, did you keep track of where you found the Rhinichthys in those different types of stream microhabitats? My labmate is working on Rhinichthys, and I'm curious if their habitat choice was consistent with their choices in the midwest and the southeast where we've sampled so far.

Yes, I have actually spent several hours watching them while feeding the mosquitos. They stay in the small pools between riffles, usually formed by small cutbanks. About 4-8 will school at the up current end of the pool where the riffle enters, noses into the current. I assume they are catching bits of food that wash down the riffle. Largest school I have seen numbered about 25-30 individuals and they were congregated at the bottom of a rather steep and fast rifle in about an 18" deep pool.
Every dew minutes they take a break and swim the length of the pool. Not always as a school, sometimes in ones and two. Also, in small groups, they will sometimes just swim up the riffle to the next pool.
Possibly of interest. We collected about 30 of them between three separate pools. When I sorted the catch, however, there was only a single identifiable male (reddish pectoral fins). Catch (in early Sept) was a 50/50 mix of full grown adults and juveniles of about 1" SL. I assume these were the fish that hatched in spring.

I would love to know where in VA you are located.

I am right between Tysons Corner and Vienna, 16 miles (26 km) from the White House. Amazing how nature finds places thrive. I was down at the creek yesterday and 9 deer, including a three point buck, were standing on the other side of the creek just 30 feet away staring at me.... and I did not have a camera.

-Shane

[2wheelsx2, posts: 924]

Nice description and photos of the habitats. I agree with the others about having kids who are interested in the hobby. My kids are 2 and 4 and have not shown that level of interest yet.

[Shane]

Had a good laugh. My daughter, she is 5, and I were just downstairs feeding the fish we caught (they are crazy for frozen bloodworm). She said, "Dad, we need some better fishes than just dace and sunfish."

-Shane