Black billowing smoke, white smokers, etc. White smoke tends to be cooler than black smoke.
Bioluminescence is incredibly low at hydrothermal vents. No endemic vent organisms that are
What is a hydrothermal vent? Area of seafloor where relatively hot fluid is invectively moving out of
water column. In order for you to have hydrothermal vent, what you need is to have a fluid that is
heated to point where more buoyant than overlying cold water. It’s not just diffusing. The rate at
which that happens is a function of density. How did seawater get into crust in first place? Ocean
floor made of cracked basalt and there are water aquifers.
This also catalyzes waterrock reactions. Water stripped of oxygen by microbes or water reacts with
rocks to remove oxygen.
Taking seawater, heating it up under pressure, in the presence of hot reduced, highly reactive
rocks. Alter chemical reactions of fluid. Vent water is HOT, north of 400 degrees Celsius. pH is low,
very acidic, but also strong acids like sulfuric acid. Organisms don’t live in that hot fluid.
Hawaiian islands sit atop a hotspot.
Hydrothermal vents are a common feature of our ocean, but represent a small area footprint. The
follow along linear features like hotspots.
Hydrothermal vents have:
High biomass thanks to a lot of local productivity (food)
Not driven by light (photosynthesis) but by chemosynthesis
Vents as an ecosystem have been around a long time, stable existence of habitat type for ~90 x
Ecological analogy = intertidal zone
Interface habitat locally
Linear habitat on global or regional scales
Highly variable on time scales from seconds to years
Small size aggregations
High secondary production
Free spawning, larvae aren’t nutrient rich but release thousands of gametes.
Each vent lives about a decade. What governs diversity in hydrothermal vents today is other
oceanic events – species on vents are relatively young, but vents have definitely been around a lot
longer, but if ocean was anoxic, then there won’t be many organisms.
We think that organisms from challenging environments (intertidal, etc) radiate into this
environment, not that deep sea species adapted to this environment. Black smoker ents – anoxic, oxygen 0. Temperature up to ~400 C, some seem to be above 400 but
above then you start to see boiling and phase partitioning. High sulfide content. Water temperature
will never be above about 400 C because excess is dumped in steam.
How does it have life? Seafloor is porous, more like metal sponge than rock, so as vent forms,
cracks around base, on side, subsurface fluid flow that create diffuse vents. Mixture of cold ambient
seawater and hot fluid from vent, c