What I Found in Brooklyn Prospect Park Lake

July 12th, 2019

I take samples from Brooklyn’s Prospect Park Lake.

A host of different critters comes with live plants and organic debris.

This piece of root comes with a jelly-like bag...

What is it?

I take it all home for further observation.

There are a lot of tiny critters roaming around in the first sample.

I recognize seed shrimp and cyclopes.

And there are many too small for me to tell for sure what they are.
But there is something big on the bottom...

That is a nymph or larvae of some insect.

Most of the tiny critters feed on algae.

I keep all samples on a windowsill exposed to direct sunlight to boost algae growth.
Cover the tank to reduce water evaporation.

Here is the second sample with the mysterious jelly-like bag.

There are much less tiny critters in this jar to start with compared to the first sample.

And yet, there are some critters.

The same nursery 8 hours later.


I am glad I keep aquariums covered - there are some jumping bugs on the water’s surface!

Let's take a closer look.
The bugs have six legs and two antennas.
They move very fast on the surface.

Here is the jar with the first sample.

 Nothing jumps here on the water’s surface, but look how much life is in the water!

That is a lot of food for the nymph.

The nymph is hiding somewhere... it could be here.

Nymphs are great hunters and masters of disguise.
 Check my previous videos for details.

These two samples expend my Summer 2019 samples collection from different ponds of New York.

Different types of critters move in ways specific to them only, making it easy to identify them.

Four days later on July 16th, the bugs are still jumping around in the second sample.

 I notice case carrying worms in the first sample.

The jumping bugs appear in the first sample on July 17th.

And they are still jumping in the other sample.

July 21st I notice tubifex.
Weirdly, I do not see the nymph even though there is not much room for it to hide.

Fast forward to September 1st.
 Here is the nymph in the first sample.
 It's amusing how big it grew in such a small space.

And there is a nymph in the second sample too!

Here is the first.

 And this one is the second.

A nymph is ready to attack at any time.

 This one just got something for a snack.
 Both are damselfly nymphs.

Water is necessary for all known forms of life.
Knowing what and how it happens in local ponds helps me to understand what it takes to build self-sustaining aquariums with fish.
Have fun and happy discoveries :)