Answer

a) Referring to tables 1 and 2, describe the results of the competition between Parus major and Parus minor when each species was competing for food from the feeder suspended by a wire hook.

Great tits are more successful / successful in 8 out of 10 encounters

[ 1 ]

b) How many observations were made of each pair of species (reference to question 2a) ) on each feeder? (HINT: This is calculated by summing the total observations at each feeder and dividing by the number of species).

10 

[ 1 ]

c) Explain the advantage of collecting data in this way. (HINT: consider how competition could be compared if the encounter were of an uneven distribution e.g. 8 of one species and 15 of another).

It allows comparisons as the number of encounters between each pair is the same  

[ 1 ]

d) Describe and suggest explanations for the results of competition between the three species on the two different feeders. You will need to refer to and consider the information contained in all the tables to answer this question.

• success (in feeding/competition) is related to body mass on wire-hung feeder;
• appropriate reference to data in Table 5;
• smaller species / named more successful on elastic-hung feeder;
• could reflect normal feeding habit / behaviour of species;
• high in tress / on smaller branches ref to Tables 3 & 4

[ 4 ]

e) Calculate the figures for relative energy requirement. (HINT: this is a calculation related to total energy requirement and body mass)

Great tit 4.13 and blue tit 4.37            both must be correct for mark      

[ 1 ]

f) Using the information in Table 6, suggest why Parus minor:

(i) has a greater relative energy requirement than Parus major

• smaller bird has larger sa:vol / terms named;
• loses more body heat / greater heat loss / greater rate of heat loss /;
• needs more food to compensate         

[ 2 ]

(ii) feeds for a greater % of daylight than Parus major.

relatively more food needed so must feed for longer  

[ 1 ]

g) Great tits and blue tits are found over a large area of Europe although Great tits are found further north than blue tits. Using the information in Table 6 and your answers to questions f) and g), suggest reasons for the wider distribution of great tits.

• Great tit has lower relative energy requirement;
• can meet needs by feeding for less time;
• farther north fewer daylight hours available / ref to data;
• limits blue tit's range / alt.     

[ 3 ]

[Total: 14 ]