miniBIOTA 1: Week 17 Update

miniBIOTA 1 as of April 10, 2024

Coastal Biome

MiniBIOTA 1 has been running for 17 weeks, and the ecosystem seems to be doing well overall. The coastal biome is particularly lush, with healthy, tall, and dense vegetation. Eight different plant species are competing fiercely for space and light. Most plants have only one individual in this ecosystem, but the coinvine (Dalbergia ecastaphyllum) got lucky. When I seeded this biome, I inadvertently collected a ton of its seeds, and now dozens of these plants are flourishing. However, there is one plant species I'm keeping a close eye on and it is the hairypod cowpea.

Hairypod cowpea (Vigna luteola (Jacq.) Benth.) sprawling across the coastal biome, its long, thin twining stems grasping for support.

This vine is a rapid grower and a fierce competitor. Unlike the other plants, which grow straight up, the hairypod cowpea spreads out across the biome, using its neighbors for support to reach the light. This strategy saves energy on building strong stems and allows it to outgrow its competitors. It has the potential to smother other plants and dominate the entire biome! We will definitely have to wait and see.

Beach Biome

Moving on to the beach, we find a very different landscape. Instead of living plants on land, dry sargassum seaweed has washed ashore, creating a temporary feast and habitat for lawn shrimp, a species of land amphipod. It's hard to say how long this resource will last, but for now, it supports a thriving food web that’s been there since the start of January this year.

Beach biome with dry sargassum seaweed and other algae onshore and living algae in the water.

The sargassum seaweed when originally seeded in the biome on January 2, 2024.

Meanwhile, underwater, various macroalgae and grasses have established themselves. These producers are crucial, providing food and shelter for other organisms. One of these is the sideswimmer, which is another type of amphipod that is fully aquatic. The sideswimmers find both food and safety here within this algae. Also, there is a key part of the food web that consists of countless and diverse plankton that lives here as well. The algae along with some types of plankton converts sunlight into the sugars and proteins that fuel the animals in the food web. The beach biome is truly a crossroads where nutrients flow between land and sea.

Sideswimmers (Amphipods)

Marine Biome

Sadly, the marine biome has seen better days. It experienced a complete ecological collapse. Initially, the biome was relatively balanced, with healthy plant growth and controlled algae levels. However, two apex predators, the naked gobies, nearly wiped out all of the sideswimmer population by picking them off easily since there wasn’t much of an algal shelter for the sideswimmers to live in.

The marine biome December 31, 2023, just before seeding additional algae and sponges. Naked goby seen at the top right.

I then created more habitat by adding algae and some beautiful sponges but unfortunately, the algae quickly overgrew and dominated the water column. It was this algae that I believed overwhelmed this biome and caused an extinction event. The algae’s nighttime respiration left too little oxygen for the bottom-dwelling sponges which caused the sponges to die. During the day, producers such as plants and algae will produce oxygen and sugars but at night, these same producers will consume their sugars and release carbon dioxide. I believe this carbon dioxide buildup ultimately asphyxiated the sponges.

After adding sponges, algae and shoal grass. January 2, 2024

Algae completely took over the biome and collapsed the ecosystem by February 2, 2024. One month later.

When the sponges died, their large bodies polluted the water, leading to a cascade of deaths. Some species were completely wiped out, while others barely survived. But life persists. Even now, energy and nutrients are being processed, mostly by single-celled algae suspended in the water.

These algae blooms follow a boom-and-bust cycle, and I've noticed that each boom becomes less intense. Experience tells me that water clarity will improve over time. As the algae consume nutrients and then die off in each cycle, those nutrients will settle to the seabed. Once most of the nutrients are out of the water column, the algae blooms will subside. This will allow marine plants access to sunlight and a fresh abundance of nutrients in the sediment. When the plants return, they'll form the foundation of a stable ecosystem, once again supporting a complex web of organisms.

The marine biome after a collapsed ecosystem. March 2, 2024

Marine Biome Hope

The marine biome’s crash was severe and devastating. A part of me wanted to pull everything out and start all over, but then I stopped myself. If I did, I’d miss the story of how this ecosystem could recover after such a catastrophic event. Every day I photograph these tanks to monitor change, and from what I can see, the algae blooms are evening out throughout the water column and lessening in color. There were some survivors from what I can tell – a lonely stone crab out of the many that were there, and 3 glass shrimps out of the original 5.

As another reason to hold out hope for this devastating loss, just days ago, I discovered that jellyfish had emerged in this biome! Somehow they snuck in as microscopic plankton that I seeded months ago and grew up in this environment. When I spotted one, I then noticed a total of four – two smaller ones about the size of the end of a pencil eraser and two larger ones around 15 mm. I have no way of knowing how they’ll fare in this system or what species they are at the moment, but for now, they seem to be growing and doing well. I’ll monitor them and share updates.

An unknown jellyfish emerged in miniBIOTA 1 marine biome

miniBIOTA 1 constantly reminds me that nature is full of surprises. The coastal biome's explosion of growth, the beach biome's reliance on a temporary resource, and the marine biome's struggle for balance... it all shows how interconnected and fragile ecosystems are. While there's sadness in witnessing the marine collapse, there's also a sense of awe at seeing life find a way, even in the most unlikely circumstances.

The story of miniBIOTA is just getting started with so much more to discover. Do you think the hairypod cowpea will take over the coastal biome? Will the beach biome thrive even once the seaweed is gone? And most importantly, can the marine biome recover? Share your predictions in the comments, and stay tuned for future updates.