E) KEEP ANTARCTICA PRISTINE
2.3 Human Impact on Animals
2.3.1 Animal Welfare Science
2.3.1.2 Animal Welfare Science – Behavioural Measures of Disturbance
of prey species vs. predator species) and individual-specific responses have to be taken into account when investigating human impact. As BROOM (1988b, p. 16) states:
“Each individual animal has several alternative methods of trying to cope with adversity and individuals differ in the methods which they favour.”
With respect to stress, JORDAN (2005, p. 518) points out: “Scientists argue that stimuli with which the animal can cope are essential to keep the coping process in good working order, and the dividing line between what is beneficial and what is harmful varies for each individual.”
The concept pursued by animal welfare science also introduces a measure more sensitive and more readily accessible than lifetime reproductive success and/or its components (e.g., life expectancy and inclusive fitness), employing proximate measures like behavioural and physiological parameters (e.g., BROOM & KIRKDEN 2004; DAWKINS 1997, 2003, 2005/ 2006; DUNCAN
2005; MENDL 2001).
In doing so, the concept challenges the assumption that negative human impact on animals can be considered inconsequential as long as the overall population remains ‘on the right side of extinction’ 61.
The validity and applicability of various behavioural and physiological parameters in the assessment of animal welfare have been reviewed by a number of animal welfare scientists (tab. 2-4). Even though the respective studies have been conducted on laboratory or farm animals, the conclusion that there is no single measure of welfare (e.g., BROOM & JOHNSON 2000; DAWKINS 2005/ 2006;
SWAISGOOD 2006/ 2007) is transferable to field conditions. JORDAN (2005), for instance points out the problems of wild animals ‘masking’ injuries, and of different species reacting to the same stimulus in different ways. SWAISGOOD (2006/ 2007, p. 141) likewise notes that “no single measure provides the ‘silver bullet’ for understanding welfare” and stresses the necessity to monitor a “suite of behavioral [sic] variables in concert” (ibid.) to characterise an animal’s state.
This has led to the inclusion of both a broad array of behavioural parameters as well as one physiological (i.e., heart rate) parameter in THISTHESIS.
61 The opposite suggestion, viz., that disturbance has sufficiently negative effects only if the species/ population as a whole is endangered, has been put forward by some researchers (e.g., NISBET 2000).
62 WEARY & al. (2006) use a classification like this for behavioural responses to pain.
2.3.1.2 Animal Welfare Science – Behavioural Measures of
Table 2-4: Reviews on Behavioural and Physiological Parameters Used in the Assessment of Animal Welfare (in Reverse Chronological Order). Small font size indicates taxa occasionally mentioned, while main study animals are represented by larger font size. Only taxa named in the main body text/ in tables have been listed. Beh.: behavioural;
Physiol.: physiological; anim.: animal(s).
Parameters Author(s)
Year Beh. Physiol. Topic of Review (Taxon, if applicable)
VONBORELL & al. 2007 – x
Heart Rate Variability for Assessing Stress and Welfare mammals: pigs, cattle, sheep, goats, horses; birds:
poultry WEARY & al. 2006 x x
Identifying and Preventing Pain
mammals: humans, laboratory animals (lab mice/ rats), dogs, cats, cattle (esp. calves), sheep, pigs, elk, deer;
birds: hens/ broilers
KIRKDEN & PAJOR 2006 x – Preference, Motivation and Aversion Tests mammals: pigs, rats, mink; birds: hens BROOM & KIRKDEN 2004 x x
Welfare, Stress & Pathophysiology
mammals: tree shrews, domestic ungulates, horses, rats, mice; birds: chickens/ hens, junglefowl, starlings, canaries
BROOM & JOHNSON 2000 x x Stress & Animal Welfare
mainly domestic mammals and birds
KOOLHAAS & al. 1999 x x
Coping Styles: Current Status in Behaviour and Stress Physiology
mammals: humans, rhesus monkeys, domestic ungulates, tree shrews, beech martens, mice, rats;
birds: chickens, great tits; fish: sticklebacks, rainbow trouts; invertebrates: octopi
RUSHEN 1996 x (x)
Aversion Learning Techniques to Assess Mental State, Suffering and Welfare of Farm Anim.
mammals: domestic ungulates, horses; birds: hens
WECHSLER 1995 x (x)
Coping and Coping Strategies – a Behavioural View mammals: rats, mice, bank voles, tree shrews, pigs, calves, dogs, polar bears, mink; birds: hens, barbary doves
BOISSY 1995 x x
Fear and Fearfulness
mammals: vervet monkeys, olive baboons, marmosets, squirrel monkeys, dogs, domestic ungulates, deer, rabbits, California ground squirrels, rats, mice; birds:
black-billed magpies, domestic fowl, Japanese quails
BATESON 1991 x x
Assessment of Pain
mammals: humans, chimpanzees, dogs, cats, horses, rats; invertebrates: insects, cephalopods
RUSHEN 1991 x x
Problems Associated with the Interpretation of
Physiological Data in the Assessment of Animal Welfare mammals: pigs, other domestic ungulates; birds: hens BARNETT &
HEMSWORTH 1990 x x
Validity of Physiological and Behavioural Measures of Animal Welfare; Focus on Problems Concerning Behavioural Measures
mammals: pigs, other domestic ungulates, horses; birds:
poultry
RUSHEN 1986 x –
Validity of Behavioural Measures of Aversion mammals: domestic ungulates, rats, dogs; birds:
pigeons
The third class of responses includes both long-lasting changes in behaviour and the short-term
‘recovery time’ before normal behaviour is again exhibited.
Incorporation of all three classes into THISTHESIS was effected by a three-period-design, comprising behaviour prior to, during, and after visitation.
It is stressed that for all three classes, knowledge on what constitutes ‘normal’ behaviour (i.e., behaviour in the absence of a given stimulus, prior to exposure) is paramount (e.g., BATESON 1991;
BROOM 2001; MAYER 2007). For this, the animals’ general ‘response repertoire’ (i.e., their evolutionary history = phylogenetic constraints) as well as possible or actual current constraints of this repertoire need to be taken into account, e.g.,
• climatic: possibility of preferential behaviours to be shown for different temperatures/ wind conditions etc. 63;
• topographical: angle of stimulus presentation or height difference to stimulus presented, available space to respond;
• annual: stage of breeding cycle;
• ontogenetic s.l.: physical maturity and learning processes;
• individual: body condition, temperament/ personality/ character
The general ‘response repertoire’ is best obtained by ethograms, either from the literature or in preliminary studies, whereas some current constraints prove more difficult to tackle, particularly those pertaining to individual animals (i.e., body condition, learning, and personality).
Measurements can be obtained with respect to the intensity64 (qualitative) or magnitude (quantitative), duration and frequency of responses, the cessation of ‘normal’ behaviour, the delay before normal behaviour is resumed and, under some circumstances, the effects of social facilitation65 (BROOM & JOHNSON 2000).
In THISTHESIS, behaviour responses to disturbance were quantitatively66 evaluated with respect to rate (relative frequency) and/ or duration, while intensity was examined qualitatively. For selected behaviours, reduction/ cessation during, and delay after disturbance were quantified to investigate their disturbance specificity.
The ‘flow’ of behaviour before, during, and after disturbance was assessed to examine changes in overall performance. In this context, ‘flow’ combines the duration of expressing behaviours belonging to a given behaviour system with occurrence and ‘smoothness’ of transitions between systems. Taken together, these components are referred to as the animal’s behavioural topography (for details see chapter 4.3.2.4.6).
63 with probable links to metabolism (e.g., energy conservation) and self-preservation (e.g., heat reduction)
64 With respect to within-parameter comparisons, this term is used a) when referring to initial differential degrees of expression (e.g., among groups pre-visit), or b) to degrees of changes without specifying exact magnitudinal values (e.g., for a gradually increasing intensity in agonistic behaviours: Bill-to-Axilla, Sideways Stare, Alternate Stare, Point, Gape). Concerning between-parameter comparisons, resting behaviour is awarded the lowest degree of intensity, while vigilance and particularly agonistic behaviours are considered behaviours of high intensity.
65 The term social facilitation refers to behaviour that is initiated or increased in rate or frequency by the presence of another animal carrying out that behaviour. (FRASER & BROOM 1990, p. 391)
66 magnitudinal changes