W4: Animal Behaviour (Conservation Endocrinology) [Dr. Madikiza]

Question 1

Conservation endocrinology?

Answer 1

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Question 2

Role of conservation endocrinology/Why is it important?

Question 3

Conservation endocrinology attributes? (4)

Answer 3

• Growth hormones.
• Reproduction.
• Homeostasis.
• Stress system.

Question 3

Application of Conservation endocrinology?

Question 3

Conservation endocrinology: Growth hormones attributes? (3)

Answer 3

• Secretion of these decrease as age increases.
• Indicate whether an animal’s environment is conducive or not.
• Indicate whether an animal is thriving or not.

Question 4

Conservation endocrinology: Reproduction attributes? (4)

Answer 4

• What are the circulating hormones & their concentration?
• What drives the production of these hormones (eg Sumatran rhino = breed rhinos to increase their population)?
• Hormone profile.
• Knowing & understanding the hormone profile of an animal/endangered animal helps us to be able to conserve that species through breeding it to increase its population.

Question 5

Conservation endocrinology: Homeostasis attributes? ()

Question 6

Conservation endocrinology: Stress system attributes? (3)

Answer 6

• We see physiological responses that drive behavioural changes.
• Glucocorticoids trigger physiological & behavioural response to help animal deal with stressors.
• Observe & understand the stress hormones in relation to the environment.

Question 7

Egs of Conservation endocrinology: Stress system? (4)

Answer 7

• Stress hormones in Hoatzin chicks.
• Penguins response to human interaction.
• Environmental toxicology.
• Response of reindeer to capture & handling.

Question 8

Explain Stress hormones in Hoatzin chicks? (6)

Answer 8

• Mullner et al, 2004.
• Similar hatching success.
• Survival is lower with tourist exposure but increases in undisturbed environments.
• Stress impeded growth & increased mortality of juveniles.
• Corticosterone is the biomarker of stress & saw baseline levels of corticosterone in undisturbed areas but it increased with tourist exposure.
• Helps managers make practical changes based on quantifiable changes.

Question 9

Explain Penguins response to human interaction? (5)

Answer 9

• Human interaction can decrease survival & cause population decline.
• Effects of adults (physiological changes): increase in stress hormone, increase in heart rate, increase in energy consumption, decrease in energy reserves, decrease in parenting capacity.
• Effects on young: unsettled/interrupted adult care caused fluctuating nest temperatures, delayed/decreased chick feeding & nest exposed to predators.
• Therefore, population declined through adult death/reduced life expectancy & reduced chick survival.
• Physiological changes led to behavioural changes.

Question 10

Things to note about Stress systems in animals? (5)

Answer 10

• Habituation occurs behaviourally through the animal getting used to the stressor.
• Habituation occurs physiologically through the animal coping via a decrease in stress hormones (almost baseline).
• Coping/stress levels differ among species (the time it takes for species to cope differs).
• Gender does not play a role in being able to adapt & cope to stressors.
• Age plays a role in being able to adapt & cope to stressors (i.e., older animals may adapt & cope better than juveniles to stressors due to experience).

Question 11

Explain Environmental toxicology? (4)

Answer 11

• DDT (persistent organic pollutant).
• Pesticides act as anti-androgens, which take up space that is supposed to be taken up by steroids.
• Pesticide influence on reproduction of animals.
• Decreases shell thickness.

Question 12

Explain Response of reindeer to capture & handling? (3)

Answer 12

• Effects of stress intensity (amount of stressor via capture & handling).
• Effects of stress frequency (increase in capture).
• Results: increased stress hormones; short-term recovery; altered behaviour (alert & avoided humans) & offspring survival & reproductive success (presence of calf at hill in summer).

Question 13

Explain Stress hormones graph? (5)

Answer 13

• x-axis = Time.
• y-axis = Stress level.
• Starts of with very low/baseline stress levels = no disturbance.
• Follows with peaks in stress hormones = disturbance/stressor in environment is present (animal is experiencing a stressor).
• Ends with decreases in stress levels and going back to baseline stress levels = animal is coping with the stressful event.

Question 14

Why could an animal be coping with a stressful event?

Answer 14

Maybe because it’s a constant stressor, which resulted in the animal habituating to it.

Question 15

Conservation endocrinology in a nutshell?