Comment by akiselev | Hacker News Reader

Comment by akiselev | Hacker News Reader

Please write to your Congress people in support of wildlife crossings [1]! Here in California especially, much of our infrastructure is aging and needs to be rebuilt in the coming decade. This is the perfect time to get wildlife crossings into the political zeitgeist so that every large highway and road infrastructure project sets aside funds to build either cut and cover wildlife crossings [2] or raised crossing [3].

Out here in East County San Diego we've got much more open space for our mountain lion population but they often face the same difficulty safely crossing the I8. Thankfully, even though they eat lots of farm animals every year (one mountain lion ate my neighbor's goat last year!), everyone tries really hard to scare them away without harming them (and especially avoid poisoning them)

[1] https://en.wikipedia.org/wiki/Wildlife_crossing

[2] https://upload.wikimedia.org/wikipedia/commons/3/3b/Wildlife...

[3] https://discoverapega.ca/wp-content/uploads/2020/08/Photo-co...

I'd love if there were human crossings too in urban areas.

You would appreciate Paris' "coulée verte". This is a 4.7 km (2.9 miles) path following an old railway and is above other roads, intersections, etc.[1]

It is really wonderful (well, outside winter maybe) - and these are the words of someone who dislikes Paris very much.

Another one is the southern one, much longer (14 km = 8.7 miles), excellent for biking.[2]

[1] https://en.wikipedia.org/wiki/Coul%C3%A9e_verte_Ren%C3%A9-Du... [2] https://fr.wikipedia.org/wiki/Promenade_d%C3%A9partementale_... (in French)

I love this idea, more congested cities should have this!

See the youtube channel Not Just Bikes[1], specifically videos like

- "Why the Dutch wait less at traffic lights" - https://www.youtube.com/watch?v=knbVWXzL4-4 argues that American traffic engineering is optimised for car movement, at the expense of pedestrians and bikes, whereas Dutch traffic engineering is to minimise conflict between vehicles and maximise movement of people overall. Leading to more complex but more efficient intersections.

- "The Dutch solution for safer sidewalks - continuous sidewalks" - https://www.youtube.com/watch?v=9OfBpQgLXUc has crossings at junctions where cars and people intersect designed so the cars visibly have to travel over the sidewalk through the people's area, instead of designed so the people have to visibly travel over the road, through the car's area.

- "Crossing the street shouldn't be dangerous, but it is" [in North America] - https://www.youtube.com/watch?v=_ByEBjf9ktY talking about length of crossings on wide road, traffic signals, priorities, etc.

[1] https://www.youtube.com/c/NotJustBikes/videos

What would make even more sense is not to have freeways in urban areas!

There’s a long, sordid history of building urban highways to both enable white flight and prevent minorities from moving into white neighborhoods.

Hopefully, we can start removing those highways and undo that damage and make larger parts of our cities vibrant places to live again.

https://www.npr.org/2021/04/07/984784455/a-brief-history-of-...

There's a ~$90 million wildlife crossing that started construction earlier this year in Agoura Hills, CA [1] where apparently many mountain lions try to cross.

It wouldn't have helped P22 since there's many roads and freeways in the 30 miles between Griffith Park, where P22 lived, and Agoura Hills but there's some progress in helping mountain lions in the area.

[1] https://en.wikipedia.org/wiki/Wallis_Annenberg_Wildlife_Cros...

I feel this is suffering from the typical US problem that public infrastructure does either not get built at all or in a super expensive way. There must be ways to build these crossings way cheaper than 90 million and place them in more locations. They only have to hold animals that at best weight a few hundred pounds.

This trend of spending millions on sinple projects is not a US problem so much as a California, New York etc problem.

$90M sounded big until I looked up the budget: https://lao.ca.gov/Publications/Report/4628What

It's measured in billions.

> They only have to hold animals that at best weight a few hundred pounds.

Uhm. I think there is some misunderstanding here. These wildlife crossings are more than just a plank going over the road. They are basically a bridge with a small patch of forest on them (or whatever vegetation matches the surrounding area).

> To encourage use by wildlife, the bridge will have lush but drought-tolerant vegetation with matte materials to deflect bright headlights and insulation to quiet the roar of cars. Fencing at each end will help funnel them onto the crossing.

I don’t know what is the fair price of a 165-foot-wide (50 m) and 200-foot-long (61 m) overpass holding up a small forest, but I know that the additional weight of the animals crossing is not a significant factor in it at all.

Now obviously if we could convince wildlife to use something much narrower and simpler built like a pedestrian bridge maybe we could drive down the costs, i’m not sure if that has been tested or not.

It has but not for mountain lions. The likes of toads and hedgehogs only need a small below-ground tube (https://en.wikipedia.org/wiki/Davis,_California#Toad_Tunnel), squirrels and marters can be helped with an above-ground rope (https://en.wikipedia.org/wiki/Squirrel_bridge)

One issue with narrow passages is that predators may learn to take advantage of them, eventually driving other wildlife away.

People on NextDoor are complaining about their children and tiny pets. Afraid that the Mountain Lion will come for them. I send them real estate links in DTLA...

Banff has quite a few of them so sounds like LA should be able to afford more than one

https://canadiangeographic.ca/articles/as-banffs-famed-wildl...

Putting a culvert under the highway would do well and it'd be cheap.

I don‘t think it‘s as trivial. I‘m definitely no wildlife expert, but the wildlife crossing that are built over here are wide bridges with a lot of greenery growing on it, so that it feels more like a small hill with a tunnel through it. And I‘d assume that there‘s reasons to build them that way - other than „all wildlife experts agree that it‘s more beautiful.“ I can imagine that some species of wildlife just don‘t crawl through culverts - or even may not fit. Can you imagine a deer getting on it‘s knees and squeeze through, antlers and all? I can‘t.

Culverts come in all sizes, even 10 foot diameter ones.

The problem with throwing $90 million dollars to build one is you cannot build very many at those prices. That means that predators will know they can hang around them picking off any herbivores that try to cross.

Culverts of various sizes can be placed - animals come in various sizes.

It's good to be curious on Hacker News, but I have to ask if you have experience in this area or are just saying things that sound reasonable to you? Despite not being an expert, I happened to hear the opposite a while back, and doing a little bit of research seems to agree that predators do not actually do this: https://www.nature.com/articles/s41598-020-67340-8. I understand the concern of "why could this possibly take $90 million, the animals don't care anyways" but I am sure that more thought has been put into this than just sticking corrugated metal culverts every so often.

The bit about predators hanging around the only access across a highway I saw in a documentary. Mountain lions would hang around under a bridge over a stream. It's the same reason predators hang around water holes, etc. They aren't stupid.

> I am sure that more thought has been put into this

I am not. Sometimes it takes someone outside the industry to see the obvious. And besides, SpaceX figured out how to launch rockets at what, 10% of the cost of NASA?

I saw a documentary once on one of those zillion dollar animal crossings, and the activists and designers simply went ape over it like they were building the Taj Mahal.

Highways are built over culverts all the time. They know how to do it. It doesn't cost $100,000,000 to do it. They don't even have to raise the highway - the highway is often raised up already on a berm of dirt to keep it from flooding.

My dad in the AF once saw that engineers devised an elaborate draining system so a highway could be built across a swamp. He suggested instead they bulldoze a berm and build the highway on that.

That reduced the cost by about 95%, and they adopted it.

Note that the civil engineers working on it all failed to see the simpler, vastly cheaper option.

Yes, it happens, and we love to see it here when it does. But I'm not sure that really qualifies what appears to be musings as anything beyond that.

Every highway wildlife crossing has been enormously expensive. But it can be pretty cheap and easy. Just put a culvert crossways under the highway. Various sizes of culvert can be used. Cheap enough to put one every thousand feet or so. Install them when the highway is being repaved anyway.

Do it for Pluie!

(https://youtu.be/Avo0-8GvBlA)

I don't think it's worth what it costs.

What's it worth, in your estimation?

We should temporarily shut down the highways until we can afford to make them safe.

Who do you think is going to go along with that?

I hope you're ok with running out of food and other essentials!

We can figure out a better solution than this.

The value and worthiness is subjective, I'd support astronomical expenses and hardship humans to improve wildlife habitat because I think its important and care about it more than most other possible things to spend money on. The reason that makes sense to me is that we have no way of bringing extinct species back, and we are killing them off at record speed. The different life forms on our planet are absolutely amazing, why shouldn't we do everything in our power, for any cost, to replenish and improve habitat for them so they can survive for our descendants to see?

why shouldn't we do everything in our power, for any cost, to replenish and improve habitat for them so they can survive for our descendants to see

you don't really mean what you've said, everything in our power? for any cost?... If we literally spent every bit of cash we had to do as you say and maximize biodiversity, our descendents would survey the biodiversity while wearing animal skins and hunter gathering and striving to someday reinvent agriculture, fertilizers, pesticides, and internal combustion engines.

yes, i'm not being serious. neither were you.

Biodiversity is part of the economy

not till its for sale.

the money you pay your housekeeper? part of the economy. you cleaning your own house? not part of the economy.

your point is valid, that it "has a value" and the economy "depends on it", and there are economists and critics who have said "we need to fix this", but definitionally economics at present is what it is and isn't what it isn't.

No I was simply using strong language to suggest that I feel strongly about it. I'm not sure where to draw the line but as a concrete example, I'd consider voting for a law which created a large tax to fund biodiversity protection. Say 10% of income for high earners, or perhaps a corporate tax, etc etc. At the end of the day its almost an aesthetic decision, I'd like to live in a world with high biodiversity and where humans are well integrated with nature, where there's animal crossings over roads and all kinds of ridiculous things like that, and I'd be willing to pay for it with some non-trivial amount. Anyway, I'm commenting on hacker news, don't take me too seriously.

Given the fast rise in mountain lion population, what are your thoughts on allowing them to be hunted?

Can you point to a good updated census of the population showing this "fast rise" event?

Given the multitude of problems facing California this is an asinine thing to focus on. Rather than hoping for a celebrity mountain lion in your neighborhood you should probably focus on the problems endangering humans in your state.

Here's the thing: sometimes focus itself is the first step towards any progress, which serves as a toe-hold which can branch out from the most seemingly silly exercises to what you really feel is a priority.

I say this considering a friend who once lamented the early space program was a waste of money, as he wore his advanced polymer clothing at work on microprocessors and GPS satellite and RF communication advances.

It felt pretty ironic.

I'd rather focus on the environment and biodiversity, you can feel free to focus on humans.

Is the same focus. Pumas would reduce the number of deer collisions that kill many people each year. Thus, they are making the roads safer for people. Saving lifes and property.

Moreover, each time there is a car crash, somebody in the road must allocate resources to clean and deal with it. Call the police, ambulances... This is expensive also. Less collisions for the city means having more money for another needs.

It is not a zero sum game.

Californians seem too be doing fine compared to where you live since that seems to be populated with people who think humans are unable to work towards more than one goal at a time. No wonder California is the home to do many advanced industries and companies, the people there have a superpower!

Society can do two things at once.

It’s not like the LAPD is going to be ushering mountain lions across the highway. And biologists/environmentalists aren’t going to be fixing crimes of poverty.

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