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INCOFISH Shifting Perspectives on Baselines Joanne Phillips Maritime Historical Studies Centre University of Hull Blaydes House 6 High Street Hull HU1.

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Presentation on theme: "INCOFISH Shifting Perspectives on Baselines Joanne Phillips Maritime Historical Studies Centre University of Hull Blaydes House 6 High Street Hull HU1."— Presentation transcript:

1 INCOFISH Shifting Perspectives on Baselines Joanne Phillips Maritime Historical Studies Centre University of Hull Blaydes House 6 High Street Hull HU1 1HA Estonian Marine Institute 3 March 2006

2 Aims and Objectives Propose ideas and pose questions for the successful placing of baselines

3 Main Point to Consider The baseline should reflect the need for world wide conservation efforts; we need both LME- and world- specific baselines

4 Structure of the Paper Demonstrate: 1.Different usages of the term Shifting Baselines 2. The importance of Shifting Baselines to the marine biologist 3. Issues with Setting Baselines 4. Discuss the value of the baseline

5 1. The Usage of the Term Shifting Baselines

6 The Definition  A baseline is defined by the point against which all other points can be compared.  A baseline is considered to have shifted where the point of reference at one time is different from at a later time because of a known or assumed progression of conditions.

7 Shifting Baselines for Marine Biologists  Long history of human intervention; short history of investigation  People adjust to continuous degradation  With time, there are reduced expectations  Need to develop historical framework  Objectives for restoration  Changing expectations requires direct local experience and education

8 Nassau Grouper (Epinephelus striatus)  The Caribbean used to have large schools  Landings are declining in Cuba & the U.S  Most anglers now accept they are inconspicuous  Its exploitation in many areas is now permanentlyprohibited

9 Decline In Marine Species

10 Shifting Baselines for Biologists  Occupied bald eagle nests in Maryland have increased steadily from 51 in 1979 to 383 in 2004  Worldwide, the bald eagle is in danger of extinction Bald Eagle

11 Shifting Baselines for Scientists  Increased levels of smog seen over cities on warm summer days  Residents of Tehran were told not to go to work or school for two days

12 Shifting Baselines for Economists  The baseline for stocks are set for each person at when they first bought a share

13 Shifting Baselines for Politicians  Politicians make more and more radical claims  When most extreme claim is dropped, others seem ‘normal’ in comparison  A new and self-interested definition of what is normal is defined

14 Shifting Baselines for the Public  Public lowers their standards to the point that they accept things that once would have been unacceptable  Expectations for themselves are changing  Expectations of nature are diminishing

15  There are millions of examples.  The shifting baseline syndrome is present in most areas of human life  The syndrome is a result of human nature

16 2. Comparison With the Marine Biologist

17 Similarities  The crucial similarity for all uses of a shifting baseline is that the point of reference has changed  This restricts the information known on the subject  Acknowledging the baseline has shifted means that the wider picture can be seen

18 3. Issues With Setting Baselines

19 Objective of Setting the Baseline  A pristine environment could never be found; man has always impacted on the aquatic resources  If we are not aiming towards pristine, what are our aims?  Is it irresponsible to set a baseline where the stocks are known to be depleted?

20 Where Should a Baseline Be Set?  According to changes in fishing (for example the start of commercial fishing, or the start or trawling)?  According to species fluctuations?  Could baselines be set every 10 years regardless of fluctuations to avoid bias?  Could it be based on the CPUE; that way boat size and power have been taken into account as well as fish caught

21 Data Fluctuations and Anomalies  Seasonal fluctuations  Natural cyclic fish stock fluctuations  Pollution can attract and repel different species  Land use change  Global warming may shift species range  Fluctuations of predators, prey and competitors  A regression line can smooth out anomalies

22 Time Series  Harper (1971) has identified three main influences of a time series: –The actual trend; the natural fluctuations of the data due to their greatest influence –Seasonal variation –Random variation; factors that have no pattern

23 Understanding the Trends  These influences need to be separated in order to fully understand the series  For example, fishing effort in Newfoundland, 1698 - 1827

24 Wars Catch CPUE

25 Other (Unknown) Factors  Condition of the stock  Pollution  Land use change  Natural species fluctuations  Change in species targeted  Power of fishing vessel  Fish-finding technology advancements

26 To What Extent Can Historical Data Be Used?  Fishing pressure is highly dependant on localised conditions that are often unknown  Were certain grounds/species protected or heavily exploited because of religion or tradition?  As much information as possible should be compiled to explain trends

27 Data Integration  If we cannot quantify qualitative historical data, what can we do with them?  Can we give each influence a numerical value?  Would this introduce bias into the results?  This will move us away from typical scientific data

28 How Representative Is the Numerical Data?  Any one measurement (i.e. CPUE) takes very little into account  Statistics can only supply trends; qualitative historical information must be used to explain these  It is not feasible to extrapolate our data back in time further than we have the data for  Does our data go back far enough for us to construct valuable baselines?

29 Spatial Developments  Not only the amount of fish fished is increasing, but also the area fished is increasing.  Fish numbers will appear to increase for a while after the area first expands.  Could an area extension be a baseline?

30 Newfoundland Expansion of Fishing Grounds

31 Area Fished 1698 - 1776 1698 1776 3 times as many fish 5 times bigger!

32 Same Species, Same Fish?  Fishing pressure changes genetic composition of species especially of size at maturity  As pressure increases, the strains that are less resilient to fishing will disappear. Man has therefore shaped the genetics of the population  To what extent can fish of 500 years ago be compared to those of the same species today?

33 What Is the Use of the Baseline?  It has been known for at least thousands of years that stocks are being depleted  Our work should not be simply more evidence of this; it should take this evidence a step forward

34 4. The Value of the Baseline The Way Forward

35 The Importance of the Baseline  What can a baseline set in the 1970s really tell us?  We need to define ‘the baseline’  Why find the baseline?

36 The Way Forward  Could we map out how the world-wide aquatic environment should look?  Large-scale restoration or significant drop in fishing effort is infeasible  World-wide comparison of different resources and how these link together  The baseline should reflect the need for world-wide conservation efforts; we need both LME- and world- specific baselines

37 Thank You J.Phillips@hull.ac.uk


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