David Cushing
Encyclopedia
David Henry Cushing FRS was an English born fisheries biologist, who is credited with the development the match/mismatch
hypothesis as an explanation for reduced fish stock
s as associated with climate change
. As opposed to other important fisheries biologists, such as Daniel Pauly
and Carl J. Walters, Cushing was a proponent of keeping fisheries open to the point of collapse.
, England. His father was an English teacher and his mother was a nurse. By way of his own desire to be a naturalist, his father's desire for him to become a diplomat, and his mother's desire for him to become a doctor, Cushing found a great interest in fisheries biology and management. Cushing also served in the British military in the Royal Artillery (1940–1945) and the Royal Fusiliers (1945–1946). Cushing is survived by his wife, Diana Antona-Traversi, whom he married in 1943, and his daughter.
After receiving his PhD, Cushing worked primarily for government organisations that oversaw the fisheries in Great Britain. For most of his career (1946–1980), he worked for the Centre for Environment, Fisheries, and Aquaculture Science (CEFAS). At CEFAS, he held the positions of scientific officer, deputy director, and as the head of fish population dynamics. His last position allowed him to focus primarily on factors influencing the stock dynamics of local fisheries and the management strategies those fisheries open.
Cushing, although not directly employed by, worked closely with the International Council for the Exploration of the Sea
(ICES). At ICES, Cushing held positions on advisory committees for fisheries management
and marine pollution
. He also chaired the biological committee and was the head of the herring workgroup.
The most prestigious position that Cushing held was that of the founding editor of the Journal of Plankton Research, which he held from 1979–2001.
was seen as a tool that could assist fisheries biologists to sample stock sizes. Cushing investigated the mechanisms that permitted the acoustic returns from the signalling devices to the fish and back. Through experimental procedures, using materials such as meat-filled condoms and air-filled balloons, Cushing determined that greater than 50% of the acoustic return was from the swimbladder of the fish. Cushing and colleagues also determined that it was possible to resolve, on the species level, the identity of a mass of fish through precise acoustic signals.
was coined by Cushing as a result of noticeable variations in fish stock
recruitment. The hypothesis focused on the timing, as a function of climate, of the bloom
s of primary producers (i.e. phytoplankton
). Blooms of phytoplankton directly influence the increased population sizes of zooplankton
, as the phytoplankton are the primary food source for zooplankton. Most pelagic fish
, in their larval stages, feed directly upon the phytoplankton and zooplankton. So as logic follows, large populations of phytoplankton will support large populations of zooplankton, and the presence of both will sustain larval fishes. As Cushing noticed, however, there are climatic influences where temperature anomalies will inhibit phytoplankton blooms, or impact the range of the bloom. When such events occur, they will have cascading effects that will influence the ability for larval fish to develop, thus reducing the number of fish that recruit into an existing population. With the previously mentioned events, the "match" portion of the hypothesis occurs when plankton blooms occur just prior the hatching of the fish larvae. In a "match" situation, the fish larvae are able to feed on large quantities of plankton, thus increasing their potential for successful recruitment. The "mismatch" portion of the hypothesis occurs when plankton blooms occur either earlier than usual, later than usual, or simply in far lesser quantities than expected. As a result, there are less prey for the fish larvae to feed upon, and the success of a recruitment event in severely diminished.
The match/mismatch hypothesis is featured in many of Cushing's writings, however the most influential purpose of the hypothesis is that of awareness of climate change
and fisheries management
. The intent of the hypothesis was to explain climate induced temperature anomalies (as a result of climate change) on fish stocks and the proper management strategies that could be associated with such changes. With some level of predictability, then, fish stocks would then avoid over-exploitation and be harvested at sustainable levels.
Match/mismatch
The match/mismatch hypothesis as described by Durant et al. , “seeks to explain recruitment variation in a population by means of the relation between its phenology—the timing of seasonal activities such as flowering or breeding - and that of species at the immediate lower level”...
hypothesis as an explanation for reduced fish stock
Fish stock
Fish stocks are subpopulations of a particular species of fish, for which intrinsic parameters are the only significant factors in determining population dynamics, while extrinsic factors are considered to be insignificant.-The stock concept:All species have geographic limits to their...
s as associated with climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
. As opposed to other important fisheries biologists, such as Daniel Pauly
Daniel Pauly
Daniel Pauly is a French-born marine biologist, well-known for his work in studying human impacts on global fisheries. He is a professor and the project leader of the Sea Around Us Project at the Fisheries Centre at the University of British Columbia. He also served as Director of the Fisheries...
and Carl J. Walters, Cushing was a proponent of keeping fisheries open to the point of collapse.
Early life
Cushing was born in AlnwickAlnwick
Alnwick is a small market town in north Northumberland, England. The town's population was just over 8000 at the time of the 2001 census and Alnwick's district population was 31,029....
, England. His father was an English teacher and his mother was a nurse. By way of his own desire to be a naturalist, his father's desire for him to become a diplomat, and his mother's desire for him to become a doctor, Cushing found a great interest in fisheries biology and management. Cushing also served in the British military in the Royal Artillery (1940–1945) and the Royal Fusiliers (1945–1946). Cushing is survived by his wife, Diana Antona-Traversi, whom he married in 1943, and his daughter.
Career
Cushing received his lower education from Duke's School (Alnwick) and the Royal Grammar School (Newcastle-upon-Tyne) and received his PhD in 1950 from Balliol College at Oxford University. His PhD dissertation focused on the vertical migration of zooplankton.After receiving his PhD, Cushing worked primarily for government organisations that oversaw the fisheries in Great Britain. For most of his career (1946–1980), he worked for the Centre for Environment, Fisheries, and Aquaculture Science (CEFAS). At CEFAS, he held the positions of scientific officer, deputy director, and as the head of fish population dynamics. His last position allowed him to focus primarily on factors influencing the stock dynamics of local fisheries and the management strategies those fisheries open.
Cushing, although not directly employed by, worked closely with the International Council for the Exploration of the Sea
International Council for the Exploration of the Sea
The International Council for the Exploration of the Sea is the world’s oldest intergovernmental science organization. ICES is headquartered in Copenhagen, Denmark, where its multinational Secretariat staff of 51 provide scientific, administrative and secretarial support to the ICES community...
(ICES). At ICES, Cushing held positions on advisory committees for fisheries management
Fisheries management
Fisheries management draws on fisheries science in order to find ways to protect fishery resources so sustainable exploitation is possible. Modern fisheries management is often referred to as a governmental system of appropriate management rules based on defined objectives and a mix of management...
and marine pollution
Marine pollution
Marine pollution occurs when harmful, or potentially harmful effects, can result from the entry into the ocean of chemicals, particles, industrial, agricultural and residential waste, noise, or the spread of invasive organisms. Most sources of marine pollution are land based...
. He also chaired the biological committee and was the head of the herring workgroup.
The most prestigious position that Cushing held was that of the founding editor of the Journal of Plankton Research, which he held from 1979–2001.
Acoustic fish detection
Acoustics were greatly improved upon during World War II so as to be used as a tool to detect unfriendly vessels and underwater hazards. After the war, acoustic detectionFisheries acoustics
Fisheries acoustics includes a range of research and practical application topics using acoustical devices as sensors in aquatic environments. Acoustical techniques can be applied to sensing aquatic animals, zooplankton, and physical and biological habitat characteristics.-Basic Theory:Biomass...
was seen as a tool that could assist fisheries biologists to sample stock sizes. Cushing investigated the mechanisms that permitted the acoustic returns from the signalling devices to the fish and back. Through experimental procedures, using materials such as meat-filled condoms and air-filled balloons, Cushing determined that greater than 50% of the acoustic return was from the swimbladder of the fish. Cushing and colleagues also determined that it was possible to resolve, on the species level, the identity of a mass of fish through precise acoustic signals.
Match/mismatch hypothesis
The match/mismatch hypothesisMatch/mismatch
The match/mismatch hypothesis as described by Durant et al. , “seeks to explain recruitment variation in a population by means of the relation between its phenology—the timing of seasonal activities such as flowering or breeding - and that of species at the immediate lower level”...
was coined by Cushing as a result of noticeable variations in fish stock
Fish stock
Fish stocks are subpopulations of a particular species of fish, for which intrinsic parameters are the only significant factors in determining population dynamics, while extrinsic factors are considered to be insignificant.-The stock concept:All species have geographic limits to their...
recruitment. The hypothesis focused on the timing, as a function of climate, of the bloom
Algal bloom
An algal bloom is a rapid increase or accumulation in the population of algae in an aquatic system. Algal blooms may occur in freshwater as well as marine environments. Typically, only one or a small number of phytoplankton species are involved, and some blooms may be recognized by discoloration...
s of primary producers (i.e. phytoplankton
Phytoplankton
Phytoplankton are the autotrophic component of the plankton community. The name comes from the Greek words φυτόν , meaning "plant", and πλαγκτός , meaning "wanderer" or "drifter". Most phytoplankton are too small to be individually seen with the unaided eye...
). Blooms of phytoplankton directly influence the increased population sizes of zooplankton
Zooplankton
Zooplankton are heterotrophic plankton. Plankton are organisms drifting in oceans, seas, and bodies of fresh water. The word "zooplankton" is derived from the Greek zoon , meaning "animal", and , meaning "wanderer" or "drifter"...
, as the phytoplankton are the primary food source for zooplankton. Most pelagic fish
Pelagic fish
Pelagic fish live near the surface or in the water column of coastal, ocean and lake waters, but not on the bottom of the sea or the lake. They can be contrasted with demersal fish, which do live on or near the bottom, and reef fish which are associated with coral reefs.The marine pelagic...
, in their larval stages, feed directly upon the phytoplankton and zooplankton. So as logic follows, large populations of phytoplankton will support large populations of zooplankton, and the presence of both will sustain larval fishes. As Cushing noticed, however, there are climatic influences where temperature anomalies will inhibit phytoplankton blooms, or impact the range of the bloom. When such events occur, they will have cascading effects that will influence the ability for larval fish to develop, thus reducing the number of fish that recruit into an existing population. With the previously mentioned events, the "match" portion of the hypothesis occurs when plankton blooms occur just prior the hatching of the fish larvae. In a "match" situation, the fish larvae are able to feed on large quantities of plankton, thus increasing their potential for successful recruitment. The "mismatch" portion of the hypothesis occurs when plankton blooms occur either earlier than usual, later than usual, or simply in far lesser quantities than expected. As a result, there are less prey for the fish larvae to feed upon, and the success of a recruitment event in severely diminished.
The match/mismatch hypothesis is featured in many of Cushing's writings, however the most influential purpose of the hypothesis is that of awareness of climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
and fisheries management
Fisheries management
Fisheries management draws on fisheries science in order to find ways to protect fishery resources so sustainable exploitation is possible. Modern fisheries management is often referred to as a governmental system of appropriate management rules based on defined objectives and a mix of management...
. The intent of the hypothesis was to explain climate induced temperature anomalies (as a result of climate change) on fish stocks and the proper management strategies that could be associated with such changes. With some level of predictability, then, fish stocks would then avoid over-exploitation and be harvested at sustainable levels.
Publications
- Marine Ecology and Fisheries (Cambridge University Press, 1970)
- Plankton production and year-class strength in fish populations: an update of the match/mismatch hypothesis (1990) in Advances in Marine Biology
- Climate and Fisheries (Academic Press New York, 1982)
- The Provident Sea (Cambridge University Press, 1988)
- Population Production and Regulation in the Sea: a Fisheries Perspective (Cambridge University Press, 1995)