Freshwater Fishes: a big observation gap

Ray-finned fishes are the most diverse vertebrate taxon, yet they seem to be one of the less frequently observed. There are exceptions – popular snorkeling and scuba destinations such as Aruba have abundant observations of reef fishes, and there are currently 8 pages of observations of billfishes (the Sailfish, three species of Spearfish, and four of Marlins), all clearly in sportfishing situations. These seem to be the exceptions that prove the rule, however; the great majority of ray-finned fishes, those which neither live on coral reefs nor are sought after as game fish, appear to be rarely observed.

To test this hypothesis, I checked the “species” tab for vertebrate observations in Iowa. The first fish did not appear until number 47, and it was a game fish, Bluegill. The second was number 66, another game fish, the Largemouth Bass. Next was Green Sunfish at number 82, then Carp at number 129.

The same procedure for Pittsburgh. This time the first fish did not appear until number 115, and it was again the Bluegill. Sacramento River: the Chinook Salmon, around number 127 (and the Bluegill five species later).

Finally, to see whether this bias extended beyond the United States, I tried Burgundy, France. The first fish to appear was the Northern Pike at number 117 – 32 observations, as compared with 494 observations of the number one species, the Common Wall Lizard.

It can’t be because of inaccessibility – the plethora of underwater observations of coral reef life shows that many iNat users have the equipment for this, and more of us live near freshwater streams than coral reefs. My hunch is that it is a lack of interest; that an iNatter with underwater gear is more likely to be interested in using it in oceans and seas. Snorkeling and scuba diving – and sportfishing – are more socially acceptable than donning a mask and lying prone in a stream less than a foot deep.

Look at what a difference it makes. Standing in a stream and photographing the fish from above will give results like this:

The minnows in a picture like this will never be identified beyond “Ray-finned Fishes.” However, by getting down to a fish’s eye view (never mind the social awkwardness), that same group of minnows looks like this:

The video I shot is even better! Now these can be identified as Ironcolor Shiners, a widespread species on the Coastal Plain, but only sporadically observed. This particular stream, Green Mill Run in Greenville, North Carolina, is popular with fossil hunters; on any given weekend in the warm season, there will be groups of them sifting through the gravel. This species of minnow is the most easily seen animal life in the stream. Yet – once again – I have made the first observation for Pitt County and one of only 5 in all of North Carolina.

I’m sure that not all of you have underwater gear. But for those of you who do, you don’t need to travel to the Great Barrier Reef to make underwater observations. What about the diversity in the “insignificant” streams and creeks close to home?


I think it is a little more nuanced that this. I certainly agree that lack of interest may be a factor, but I doubt it is the key factor.

Freshwater fish biodiversity is much more diffuse than fish diversity at a coral reef. I could spend several days hunting down the 15 or so species of fish that occur in my local stream, but one could get perhaps double that in just a few hours at a reef.

This is likely more a case of a relative few observers making a high volume of observations and/or iNatting occurring as the side activity, not the focal activity of people visiting the coral reefs (the number of observations I’ve made while doing a different focal activity far outnumber the observations I’ve made while specifically looking for things to record on iNat, because iNatting is mostly something I do as I naturally come across things).

I think inaccessibility, both real and imagined, are the primary contributing factor. I like your post because it highlights that much of that inaccessibility is imagined. You don’t need fancy equipment to go out and observed freshwater fish; you just need patience and the right methodology.


I would like to observe more aquatic species, but I live in Delaware, US, and the water quality isn’t great and most freshwater locations are not considered safe to swim in, due to pollution, bacteria, toxic algae, etc. The water is also not very clear, but fish can sometimes be seen in shallow water in sunlight. I always take a picture when I see fish, though. I have 34 local species. Any recommendations for observing more fish would be appreciated!


(Edit to correct spelling) Well, I would like to get more fish - they are important vertebrates! But I find it hard to get both fresh water and salt water fish pictures from the shore.

Less than half get an ID, which I get as they are not sharp pictures.

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Hi @jasonhernandez74! :wave:

As @swampster said, and as @cammie and @teellbee confirmed, it IS because of a lack of accessibility. We are interested! :fish: :tropical_fish: :heart_eyes:

Some of the equipment that I’ve used in the “ancient past” (in the pre-iNatting days), to get my hands on fish, and to get my camera on fish, include:

  • Trawl nets
  • Beach seines
  • Purse seines
  • Cast nets
  • Gill nets
  • Boats
  • Dip nets
  • Fishing rods
  • Minnow traps
  • Etc.

That’s a lot of gear! You could fill a tractor trailer with the gear required for fish observations!

But there is a solution to the problem that you mentioned:

One solution is that many people are already using that gear all the time: fishermen, campers, etc. It’s a matter of building awareness that iNaturalist exists. To anyone reading this (not just @jasonhernandez74), you can build awareness of iNat, in this fishing population, in many different ways. Here are a few ideas:

  • You could run an iNat booth at an outdoors show, a fishing show, or a camping show
  • You could make more iNat-related posts on social media
  • You could post in fishing forums and message boards
  • You could volunteer at fishing tournaments
  • You could engage local campgrounds
  • You could network with local outdoors stores, like Bass Pro Shops
  • You could network with your state department of game and fish

Let’s dive into these outreach methods! We can cast a wide net and reel in a wave of observations from fishermen and campers. Tight lines!


How do you do that without scaring them away? What about cloudy water?

With my long lens if I get at the right angle I can get a shot where you can see the side of the fish. Only works for fish that hang out at the top of the water.
But sometimes the fish is not entirely underwater!


I don’t have any underwater gear and - for the reasons you mentioned - find it difficult to get good photos of fish. However, it’s always a great feeling any time the conditions are just right to decent photos from outside the water.

Taken from a pedestrian bridge overlooking a stream passing through a city of 400,000:
Taken from stepping stones or from the streambank of the same stream:
Taken at a lake while using a macro lens:
Taken at a mountain stream:
Taken at the beach:

Similar to @lappelbaum, I’ve also encountered a few fish that weren’t underwater:
(Granted, including a mudskipper here is kind of cheating …)


Are there any solutions for photographing underwater from the river or stream bankside? Maybe an underwater camera attached to a selfie stick with a remote shutter and monitor?

I think equipment and accessibility are key factors for me - taking photos into water from dry land hasn’t worked very well so far.


Some organisms can’t be easily photo’d unless you have them in hand. I’ve not photo’d freshwater fish all that often but I’ve certainly collected quite a diversity using one-or two-person seines in streams or dip nets in smaller bodies of water. I often caught fish in hoop traps set for freshwater turtles. You might need to check with your regional wildlife agency about the legality of using such equipment.


Sometimes the fish is entirely out of the water—and in a tree!

We have photograph fish entombed in ice:

Another idea we had and haven’t tried yet is to ask anglers fishing from shore if we can photograph their catches


It’d be nice if there were such a thing as an underwater camera trap. Unfortunately, anything left in the water for an extended is likely to either come loose and be carried downstream or become covered in algae and sediment. You could potentially get better photos from above the surface of a clear stream, though, if you fix a rigid ring at the surface of the water (something like the metal ring of a cheesecake pan) to create a viewing window where the water is calm.

I think with many water bodies, though, turbidity prevents most in situ observations, and we have to rely on extractive methods to observe the aquatic life under the surface.


Around me, I believe you need a permit even for dipnetting which is something that would get you a lot of species that aren’t usually observed. Not to mention that river access is hard to come by being mostly developed.

I’ve spoken to anglers when I’ve come across them while iNatting and spoken to them about it. I sometimes get pushback because they are worried that someone will “steal their spot” if they see everything they catch there. That attitude may explain the only common gamefish being posted even by anglers aware of iNat


I find that if I stay in one place in the water, the fish become curious. One of the two videos is of the minnows coming up and nibbling at my swimsuit.

That is a problem. There are places where I doubt I will ever be able to observe fishes because of either suspended sediment or algal growth.

At today’s population levels, someone already has.

One thing I forgot to add, an important ethical consideration. Not too far from where I filmed those minnows, I saw a Centrarchid (possibly Pumpkinseed?) on its nest. So if you’re going to be walking around in water bodies, please find out which fish species have nests and what their nests look like so that you can avoid trampling them.


I’d add that many people aren’t going out specifically to make observations, they’re simply thinking to take a photo when they happen across something neat. Even if you don’t need a ton of equipment to get pictures of fish, they’re often not as immediately noticeable as things like plants, mammals, and birds, which all tend to live and move within the same environments that humans do. Thinking about the hiking trails I know, you often have to take a detour from the main trail itself to get close enough to any body of water to see what’s living in it.


DIY underwater drop cameras are a thing, although probably not something a normal person would want to put the effort or expense into. (I built one myself and I’m happy to talk about some of the challenges, in addition to what you mentioned, if anyone is interested.)

A viewer like you mentioned is a more practical option. It can be as simple as a cake ring, or a PVC periscope. Look at ice fishing cameras if you’ve got money to burn. If you prefer to live dangerously, stick your cell phone in a Ziploc bag.

However people do it, it would be great to see more in situ photos of freshwater fish. Tag them with the spectacularly underutilized Underwater observation field for bonus points.


I’ve done this a couple of times with good results. Usually, people are pretty amenable to letting me get a quick shot or two.


Let’s not forget bird watchers. Log those osprey kills, try and photograph what a kingfisher or heron is catching. I’ve seen a few bird obervations on here and asked the user to duplicate them for the prey items.

Most of my fish observations come from fishing. I’m always wary of posting them as it’s not always an activity that’s supported in conservation. I haven’t had any negative comments yet though.


Yes, please!
Prey of North American Herons, Egrets, & Bitterns


One easy help that I don’t think has been mentioned yet is using a polarizing filter. Just like fisherfolk often have polarized sunglasses, these filters for a camera do a good job at eliminating a good chunk (though not all) of surface glare from water. They make it easier to get decent pics from shore.

On a broader note related to opportunity, as @slugcycles was talking about, unless people are going out specifically to make aquatic observations, they are much less likely to observe fish for the simple reason that, on land, where most people are, fish are present on a tiny proportion of the landscape. Unless folks are on a trail next to a body of water, they almost certainly won’t have the opportunity to make fish observations (barring the bycatch observations from birds as @wildedges mentioned). So just based on the proportions of where people physically are present on Earth, I think fish observations will always be low compared to other terrestrial organisms.


I’ve been thinking of taking up microfishing/species fishing. It is the targeting of the highest variety of non-game fish for observation purposes. They even sell small acrylic photo tanks for taking pictures of fish and other aquatic species while you have them out of the stream or pond. It seems like fun.