Fish Doorbell | Hacker News Reader

Fish Doorbell

dutchreview.com

112 pointsyamman32 comments

For places humans have dammed a river, a fish ladder can be installed to let fish continue to swim upstream: https://en.wikipedia.org/wiki/Fish_ladder. I wonder why that's not used here.

Perhaps it's related to this being a _lock_, not a dam. In addition to having water loss from the lock, the middle part of the lock goes up and down, so you'd have to have separate fish ladders for each part.

For the most fun fish transport I've seen, check out the Salmon Cannon: https://www.youtube.com/watch?v=nopg9JSTTzg and https://www.youtube.com/watch?v=eGzdOpCisnQ. It uses a pressurized tube to transfer salmon from the low to high side. In the second video, the distance is over a kilometer.

From the Wikipedia article you referenced to:

> Fish ladders have a mixed record of effectiveness. They vary in effectiveness for different types of species, with one study showing that only three percent of American Shad make it through all the fish ladders on the way to their spawning ground

I guess that’s what they call artificial selection pressure.

If we're going the route of applying selection pressure to other species for human amusement, then we should just go straight to unicycles.

... so, you think fish will need unicycles more than they do bicycles?

Are you aware that computers are a “bicycle for the mind”?

It's more of an awareness campaign than purely for the benefit of the fish. One of the people involved with it said in a Dutch interview that there are other locations where this is automated.

There are some locks in Seattle with a ladder: https://en.wikipedia.org/wiki/Ballard_Locks#Fish_ladder

They achieved this by putting the ladder on the opposite side of the channel from the locks.

So the think with salmon is that they orient by sound. If they don’t know where to go next they head toward the sound of running water - the next rapids upstream. To get them to traverse a dam you have to make waterfall noises in the correct spot and not make them in the wrong spot. I believe I’ve read of people using this to trick salmon into going through locks, but the ladders seem to be simpler.

I'm from the city in question and not that happy the municipality chooses to throw away money on a vanity campaign. If all they wanted was to transport fish this webcam wouldn't be necessary.

Wouldn't an automated system cost more money than this system, which is essentially just an underwater webcam?

This sluice is ornamental. Water levels aren't any higher or lower before or after. The 'automated solution' would just be to open it most of the time and perhaps lay down a small footbridge so pedestrians and cyclists can still cross it.

> Water levels aren't any higher or lower before or after.

Yes they are. It's a fully functional sluice, and the water level on the city centre-side is higher than the water level of the Vecht outside the city. They cannot open both sluice doors at once. During summer, sluice operators are active all day to guide boats through, and they cannot pass the sluice after the operators' working hours.

(Also, the footbridge already exists.)

It's a tiny monumental lock dating back to the middle ages. It has a history going back to the 1300s, as do the buildings around it.

Adding a traditional fish ladder isn't really a realistic option at this location.

If I interpret this correctly, the fish don't hit the doorbell -- human bystanders see fish and use their mobile devices to hit the doorbell.

There's probably a solution that could detect the fish without human intervention, but it seems like one of the points is to help the citizens engage more an build awareness of the human/wild-life interaction.

From the article:

> Why did the city decide to go for a digital doorbell instead of an automatic sensor? Because it’s a lot more fun, of course.

So Dutch.

What a nice idea. I mean one could probably automate the button with machine learning (it just needs to look for fish). But damn, it is wholesome to manually watch and help them.

Here is the link to the live stream with the "door bell" button.

https://visdeurbel.nl/

That’s the point. This creates awareness about the life in the water and hopefully it helps to reduce people throwing trash in it

As the article says, it's a lot more fun this way. I love it.

Also, looks like the live stream is currently being hugged to death. Maybe it wasn't such a good idea to post this here, after all ;-)

> live stream is currently being hugged to death

Perhaps someone should ring the doorbell so it flows again…

Thanks for the link. I just enjoy watching fish. I'll visit once traffic dies down a little here.

Aw, it doesn't show a button for me...

I thought this had to be an April fools day prank, but apparently it went live a couple of days ago and was on the news.

Anyway, this means a second stream beside the Iceland vulcano on my 2nd monitor. It's about 1km. from where I live, and I had to learn about it on HN...

Edit: link to cam is on https://visdeurbel.nl/

More accurately, they have created a crowdsourced digital fish doorman.

Which is, incidentally, the name of my next acid jazz band.

I didn’t manage to get past the Dutch cookie consent. How do I say no cookies or legitimate interest in Dutch?

A surprisingly high number of links posted to HN can be read while having js and cookies disabled. It’s not for everyone, but it does work to bypass the consent popup in this case as well.

This is a tricky one.

There is one route to revoke consent and another route to object to legitimate interest, and it doesn't seem that you can precisely follow both routes. I assume the second option does both, but it's not clear.

I've seen this same pattern in English also, so I'll include my translation:

Meer Opties (More Options) -> Gerechtvaardigd Belang (Legitimate Interest, small link on bottom left) -> Bezwaar Tegen Alles (Object to All) -> Opslaan en Afsluiten (Save and Close)

You should try setting your user agent to default block javascript + cookies. It's actually not that bad. I'm not a zealot, I just whitelist sites as I come across them that don't work without those things. In the end, most websites I visit work better without javascript/cookies rather than degrading in performance. For example basically every newspaper that prevents you from reading too many articles lets you read as many as you want without javascript running.

I read the article, but I feel like I still missed the point. Why are they preventing the fish from just swimming through on their own? Is this only to raise local awareness or is there some benefit I missed for the fish?

It's a sluice, so the fish can only swim through when it's open. In the summer it's regularly opened for passing boats, but during winter they have to do so explicitly just for the fish.

I am so envious of your country on so many levels. I used to be proud of mine?

Even the fish from Amsterdam are trying to get to the Culture Boat.

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