The Human Impacts Database

A collection of useful numbers for quantifying the impacts of the human presence on Earth.

This quantity is a single measurement of the quantity at a given point in time (2021).


Value:		≈ 0.06 - 3 × 10¹² kg see this value in other units This is equivalent to... ≈ 0.06 - 3 Pg
HuID:		60653
Relevant Year(s):		2021
Summary:		This value is an estimate of global oceanic mammal biomass. This mass may be underestimated due to difficulty in observing animals far below the surface, poor estimates of geographic range of species, and human capture.
Method:		This estimate is based on survey data of population abundance for about 2/3 of species. For the remaining third of species, abundances were estimated from regression analysis based on the surveyed species. They developed a relation between population density and biomass and used to estimate densities of the 1/3 of species for which no survey data existed. The measure of uncertainty reported is based on other estimates of marine mammal biomass, which vary by a factor of about 3. Here, the uncertainty interval covers a factor of about six, which the authors report as a conservative estimate.
Source:		Hatton, I.A., Heneghan, R.F., Bar-On, Y.M., Galbraith, E.D. The global ocean size spectrum from bacteria to whales. Sciences Advances (2021)
Dataset:		Estimate of oceanic biomass by category (summary_data_table_with_aggregates.csv) global resolution
Original Data License:		CC-BY 4.0
Added By:		rbanks