How to help us count shad

Help us monitor the annual shad migration by counting the number of fish successful swimming upstream at the notch in Upper Lode weir.

Become a citizen scientist

We need the help and support of members of the public to help us monitor the rare twaite shad during their annual migration on the River Severn. So, if you have a few minutes to spare, please help us count shad and become a citizen scientist!

The visual count by citizen scientists is an important part of our monitoring programme. It provides data and helps calibrate other automatic counting techniques. You will help us understand the population dynamics of this endangered fish and track its fortunes from year to year.

We would love you to register on the website so that we can show you some appreciation for your shad-counting efforts. You will also be able to join our leader board of other shad-loving citizen scientists. Simply register where prompted.

But don’t worry if you just want to give it a try first, or prefer to be a stealth-scientist. You don’t need to register to contribute your count.

Count all the shad that make it upstream over the weir.

Fish migrating upstream will be swimming from the bottom to the top of the screen. We only want to count the shad that successfully cross the notch i.e. swim entirely out of view at the top of the screen.

If there are any shad on-screen at the start of the video please do include them in your count if they successfully swim upstream (out of frame at the top . At the end of the video, do not count fish are still visible on-screen.

Ignore any fish that swim back downstream and don’t count those fish that don’t make it.

If you spot any fish swimming back downstream (from top to bottom in the video), simply ignore these fish. We are only counting fish swimming upstream.

If you see any shad that don’t make it all the way across the notch (but drop back downsteam) as shown in this video – please do not include them in your count.

If you don’t see any shad, submit a count of zero

Twaite shad like to shoal and move as a group in the river. This means you may be lucky and see several shad in your video, or view a video clip with no fish in it. If you don’t see any fish please record a count of zero. The zero counts are just as important in our data set. And don’t give up, do keep watching more videos for another chance to see shad.

If there are too many fish, then pause, repeat, or try viewing on full screen

If there are many fish all at once making it hard to count, you can pause or replay. You can also open the video in full screen. All of these controls are visible in the control bar along the bottom of the video which shows once you have hit play (the arrow symbol).

In this video clip you will also notice a shad moving upstream to the left of the white board. If you see any fish off to the side like this, that do make it upstream (all the way out of view at the top) then please do include these fish in count.

Please use the comment box if you need to tell us something or are unsure. For example, if you spot something unusual (such as an otter, or bird, or other fish species), or if you find it impossible to count the fish (perhaps because the video is too dark, or too many fish all at once).

Other fish species you might spot

You might occasionally see some other kinds of fish – watch the video for some of the more common examples. If you are lucky enough to see something other than a shad please don’t include them in your shad count, but do let us know in the comments box so we can review the footage.

Watch the video to see examples of these fish swimming over the notch:

Salmon are much bigger than shad and seem to swim with much less effort.

Lamprey have a long, thin silhouette and they sometimes pause, using their sucker-mouth to hold themselves in place.

Barbel these coarse fish are bigger than shad, both in length and thickness in the body. Their silhouette from above is wider and less elongated than a shad.

Let’s start counting shad!