QUESTION 6 (3 marks)
The Bush Stone-curlew is a large, mainly nocturnal, ground-dwelling bird found on Hamilton Island. Bush Stone-curlews have a wide-ranging diet but prefer to feed on insects, molluscs, small lizards, seeds and, occasionally, small mammals. During the breeding season, nesting birds will search for food in the vicinity of the nest site.
a) Identify one factor that would influence carrying capacity on the island.
[1 mark]
b) Discuss one way the carrying capacity of the Bush Stone-curlew on Hamilton Island could be positively or negatively affected in the future.
[2 marks]
QCAA guide · typeset solution
QCAA sample response and mark allocation
6 | a) | Food availability | • identifies a resource or service of an ecosystem [1 mark] | Others include: food availability water availability space, e.g. appropriate shelter, nesting sites space may also include restrictions due to abiotic environmental conditions, e.g. salt water, pollution, erosion, tidal flow or other suitable response consistent with a reasonable understanding. |
6 | b) | A future limiting factor, negatively affecting the carrying capacity, could include development on the island (new villas, roads etc. taking away space for the curlew’s nesting sites). | • describes a relevant cause [1 mark] • discusses the relevant consequence [1 mark] | Relevant causes that could negatively affect carrying capacity may include: food availability (including competition, climate issues, disease) water availability (including pollution, drought, habitat destruction) space (including nesting sites, finding mates, habitat destruction). Relevant causes that could positively affect carrying capacity may include: food availability — as they have a wide- ranging diet, food from tourists (e.g. fish scraps) and rubbish, or increased lights at night attracting insects for food etc., or changes to the flora and fauna (introduced species, agriculture activity) may actually increase the food source availability artificial habitats may be made that benefit the curlew nesting sites, e.g. under boardwalks water may become more available with installation of tanks, water retention ponds or irrigation systems. |
QCAA sample response and marking criteria reproduced from the official guide.
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