University Of Tasmania

File(s) under permanent embargo

Unshifting the baseline: a framework for documenting historical population changes and assessing long-term anthropogenic impacts

journal contribution
posted on 2023-05-20, 11:37 authored by Rodrigues, ASL, Monsarrat, S, Charpentier, A, Thomas BrooksThomas Brooks, Hoffmann, M, Reeves, R, Palomares, MLD, Turvey, ST

Ecological baselines—reference states of species' distributions and abundances—are key to the scientific arguments underpinning many conservation and management interventions, as well as to the public support to such interventions. Yet societal as well as scientific perceptions of these baselines are often based on ecosystems that have been deeply transformed by human actions. Despite increased awareness about the pervasiveness and implications of this shifting baseline syndrome, ongoing global assessments of the state of biodiversity do not take into account the long-term, cumulative, anthropogenic impacts on biodiversity. Here, we propose a new framework for documenting such impacts, by classifying populations according to the extent to which they deviate from a baseline in the absence of human actions. We apply this framework to the bowhead whale (Balaena mysticetus) to illustrate how it can be used to assess populations with different geographies and timelines of known or suspected impacts. Through other examples, we discuss how the framework can be applied to populations for which there is a wide diversity of existing knowledge, by making the best use of the available ecological, historical and archaeological data. Combined across multiple populations, this framework provides a standard for assessing cumulative anthropogenic impacts on biodiversity.

This article is part of a discussion meeting issue ‘The past is a foreign country: how much can the fossil record actually inform conservation?’


Publication title

Philosophical Transactions of the Royal Society B: Biological Sciences










Institute for Marine and Antarctic Studies


Royal Soc London

Place of publication

6 Carlton House Terrace, London, England, Sw1Y 5Ag

Rights statement

Copyright 2019 The Authors

Repository Status

  • Restricted

Socio-economic Objectives

Assessment and management of Antarctic and Southern Ocean ecosystems