Fisheries — Paper 2 · IGCSE Marine Science (Maldives only) 0697

1 Table 1.1 shows the annual global tuna catch every five years between 1985 and 2015. Table 1.1 year annual global tuna catch / million tonnes 1985 1.7 1990 2.1 1995 3.0 2000 3.5 2005 3.3 2010 3.2 2015 3.1 (a) (i) Plot a graph to show the annual global tuna catch between 1985 and 2015. Join your points with ruled, straight lines. [5] (ii) Outline the trends in annual global tuna catch between 1985 and 2015. … … … … [2] (iii) Suggest three reasons for the change in annual global tuna catch between 2000 and 2015. 1 … … 2 … … 3 … … [3] (b) The global demand for tuna in 2025 is predicted to be greater than the catch. Tuna aquaculture is being developed to meet the demand. Kingfish aquaculture is being used as a model for tuna aquaculture. Gross annual income is the total amount of money received from sales before costs. Table 1.2 shows the gross annual income from kingfish sales and the annual cost of labour and maintenance for kingfish aquaculture business. Table 1.2 gross annual income from kingfish sales annual cost of labour and maintenance / USD ($) / USD ($) 550 000 425 000 (i) Use Table 1.2 to calculate the annual profit of the kingfish aquaculture business. … USD ($) [1] (ii) The cost to start up a kingfish aquaculture business is estimated to be $500 000. Calculate the number of years it will take the kingfish aquaculture business to recover the start-up cost. … years [1] (iii) Suggest three factors that could increase the length of time taken to recover the start-up cost. 1 … … 2 … … 3 … … [3] [Total: 15]

15 marks

This question in 0697/20 May/June 2021

3 Sea cucumbers are an important commercial catch that are often caught by beam trawling. (a) Name the external features of a sea cucumber and describe their functions. … … … … … … … … … … … … [6] (b) Describe the method and environmental impacts of beam trawling. … … … … … … … … … … [5] (c) Describe methods of conservation that may be used to protect sea cucumbers. … … … … … … … … [4] [Total: 15]

15 marks

This question in 0697/20 May/June 2021

4 (a) (i) Explain the role of exclusive economic zones (EEZs). … … … … … … [3] (ii) Name two international organisations involved in fisheries management and conservation, and outline their aims. … … … … … … [4] (b) Discuss how different factors affect the price of seafood products. … … … … … … … … … … … … … … … … … … [8] [Total: 15]

15 marks

This question in 0697/20 May/June 2021

1 Table 1.1 shows information about the catch for yellowfin tuna using pole and line. Table 1.1 year catch fishing effort catch per unit effort (CPUE) / tonnes / days / tonnes per day 2013 19 000 63 247 0.30 2014 18 000 36 144 0.50 2015 16 000 22 877 0.70 2016 8500 29 061 0.29 2017 17 500 25 042 0.70 2018 18 200 26 640 (a) (i) Draw a line graph to show the catch each year between 2013 and 2018. Join your points with straight, ruled lines. [5] (ii) Describe the change in catch between 2013 and 2018. … … … … [2] (iii) The catch per unit effort (CPUE) was calculated using the formula: catch catch per unit effort (CPUE) = fishing effort Use Table 1.1 to calculate the CPUE for 2018. CPUE = … tonnes per day [1] (iv) Suggest two reasons for the change in CPUE between 2015 and 2016. 1 … 2 … [2] (v) The fishing effort was measured as the number of days of fishing of all the boats in the fleet. Suggest why this method of determining fishing effort may not be an accurate measure of the true effort used in catching the fish. … … [1] (b) To conserve fish stocks, scientists investigated the effect of building artificial reefs. An artificial reef was placed on the sea bed. Each year, the scientists recorded: • the percentage of the artificial reef covered with coral polyps • the number of different species found on and around the reef • the catch of rainbow runner fish. The results are shown in Table 1.2. Table 1.2 year percentage of artificial number of different catch of rainbow reef covered with coral species found runner fish / kg polyps 2008 2 5 435 2010 10 14 415 2012 30 22 490 2014 40 28 550 2016 50 27 645 The coral on the reef contained zooxanthellae. Rainbow runner fish are high trophic level predators. Use the data in Table 1.2 to suggest an explanation for the change in catch of rainbow runner fish over time. … … … … … … … … [4] [Total: 15]

15 marks

This question in 0697/20 May/June 2022

4 (a) (i) Describe the use of pelagic long-lines. … … … … … … [3] (ii) Explain the principles of fish aggregating devices (FADs). … … … … … … … … [4] (b) Describe the uses of three named navigational aids found on fishing boats. … … … … … … … … … … … … … … … … [8] [Total: 15]

15 marks

This question in 0697/20 May/June 2022

1 Anchovies are small pelagic fish that feed on plankton. Skipjack tuna are predatory fish that feed on many species, including anchovies. Scientists analysed the catch of anchovies and the catch of skipjack tuna from an area of the Pacific Ocean over five years. The results are shown in Table 1.1. Table 1.1 catch of fish / thousand kg year anchovies skipjack tuna 2012 25 10 2013 35 15 2014 50 22 2015 25 30 2016 10 25 (a) (i) Plot a graph to show the catch of anchovies and the catch of skipjack tuna between 2012 and 2016. Join the points for each set of data with ruled, straight lines. [5] (ii) Describe the change in catch of anchovies between 2012 and 2016. … … … … [2] (iii) Use the data in Table 1.1 to suggest why the catch of skipjack tuna changed between 2012 and 2016. … … … … … … [3] (b) Scientists examined the gut contents of the skipjack tuna. The percentage of skipjack tuna with anchovies in their gut is shown in Table 1.2. Table 1.2 year percentage of skipjack tuna with anchovies in their gut 2012 75 2013 85 2014 65 2015 55 2016 (i) In 2016, 500 skipjack tuna were analysed and 210 were found to have anchovies in their gut. Calculate the percentage of skipjack tuna with anchovies in their gut in 2016. … % [1] (ii) Suggest two reasons why gut content analysis of the skipjack tuna may not be an accurate measure of the population of anchovies. 1 … … 2 … … [2] (c) Suggest two methods used by a government to keep the fishing of anchovies sustainable. 1 … … 2 … … [2] [Total: 15]

15 marks

This question in 0697/20 May/June 2023

3 (a) Name one boat building material and describe one property that makes it suitable for this. material … property … … [2] (b) Describe the method and the environmental impacts of pelagic long‑lining. … … … … … … … … … … … … … [5] (c) Outline the principles of a four‑stroke diesel engine. … … … … … … … … … … … … … … … … … … … [8] [Total: 15]

15 marks

This question in 0697/20 May/June 2023

6 Pelagic trawling is a method of fishing. (a) (i) Describe the method of pelagic trawling. … … … … [2] (ii) State one negative environmental impact of pelagic trawling. … … [1] (b) Benthic trawling along the seabed is another method of fishing. One impact of benthic trawling is increased sediment release from the seabed into the water column. The sediment affects light penetration. Describe an investigation to test the impact of benthic trawling on light penetration in the water column. Your method should include a relevant safety precaution. … … … … … … … … … … … … … … … … [6] [Total: 9]

9 marks

Mark scheme: 6(a)(i) any 2 of: towing a net from boat ; net in water column / AW ; fish are hauled on boat (in net) / AW ; 6(a)(ii) bycatch ; OR overfishing ; 1 Question Answer Marks 6(b) any 6 of: area with and area without trawling / AW ; Secchi disc / description of one / AW ; place (disc) into water / AW ; measure length of rope when disc disappears / AW ; raise disc until it appears and record length again / AW ; calculate mean depth ; repeat ; same time of day / same weather / same light / AW ; same disc shape / size / AW ; same type of seabed / AW ; appropriate safety precautions e.g. lifejackets / GPS / AW ; 6

This question in 0697/21 May/June 2024

2 Mackerel are pelagic fish that are often caught by using purse seine nets. (a) Describe purse seine net fishing. … … … … … … [3] (b) Fig. 2.1 is an image of a mackerel, Scomber scombrus. X A Fig. 2.1 (i) In the space below, make a large, accurate drawing of the mackerel shown in Fig. 2.1. Do not include the markings. [4] (ii) State the name and the main function of the fin labelled A in Fig. 2.1. name of fin A … main function of fin A … [2] (iii) The magnification of the image in Fig. 2.1 is × 0.85. Calculate the actual length of the mackerel in Fig. 2.1 along the length of the line labelled X. Give your answer in centimetres and to the nearest whole number. Show your working. actual length of mackerel = … cm [2] (iv) The binomial name of this mackerel is Scomber scombrus. Complete Table 2.1 to classify the mackerel. Table 2.1 classification group name Eukarya … kingdom … genus … species … [2] (c) Mackerel live within the sunlight zone of the open ocean. (i) State two abiotic conditions of the sunlight zone. 1 … 2 … [2] (ii) This mackerel is a typical example of a fish species that is adapted to live in the sunlight zone. Explain one adaptation of fish species in the sunlight zone. … … … … [2] [Total: 17]

17 marks

Mark scheme: 2(a) any 3 of: release net into sea / release net from boat / AW ; boat circles round (so net surrounds) fish / surround the fish with the net / AW ; drawstring / ropes, pulled to, close net / close bottom of net / AW ; ref. to net (with catch) pulled on board boat ; 2(b)(i) large drawing ; neat, clear lines that are not broken lines and no shading ; (proportions of all correct) width of tail is more than width of body ; operculum, pectoral fin, caudal fin, eye, and mouth present in correct locations ; 4 2(b)(ii) name: caudal (fin) ; function: thrust / move fish forward / drives it forward / AW ; 2 2(b)(iii) 16 (cm) ;; OR correct measure of length of line X ; division of length by 0.85 ; 2 2(b)(iv) domain (Eukarya) + (kingdom) animals (genus) Scomber + (species) scombrus 2 Question Answer Marks 2(c)(i) any 2 of: light / sunlight ; high oxygen (concentration) / AW ; low pressure ; variation in temperature / variable temperature / AW ; 2 2(c)(ii) Any 2 of: counter-shading / camouflage / AW ; escape from predators / catch prey / AW ; OR fast swimmers / streamlined / AW ; escape from predators (as there is no shelter) / catch prey ; OR generalist feeding / can eat many different types of food / AW ; due to competition / availability of food / AW ; OR migratory ; to reach breeding / feeding grounds / AW ; 2

This question in 0697/22 May/June 2024

2 Mackerel are pelagic fish that are often caught by using purse seine nets. (a) Describe purse seine net fishing. … … … … … … [3] (b) Fig. 2.1 is an image of a mackerel, Scomber scombrus. X A Fig. 2.1 (i) In the space below, make a large, accurate drawing of the mackerel shown in Fig. 2.1. Do not include the markings. [4] (ii) State the name and the main function of the fin labelled A in Fig. 2.1. name of fin A … main function of fin A … [2] (iii) The magnification of the image in Fig. 2.1 is × 0.85. Calculate the actual length of the mackerel in Fig. 2.1 along the length of the line labelled X. Give your answer in centimetres and to the nearest whole number. Show your working. actual length of mackerel = … cm [2] (iv) The binomial name of this mackerel is Scomber scombrus. Complete Table 2.1 to classify the mackerel. Table 2.1 classification group name Eukarya … kingdom … genus … species … [2] (c) Mackerel live within the sunlight zone of the open ocean. (i) State two abiotic conditions of the sunlight zone. 1 … 2 … [2] (ii) This mackerel is a typical example of a fish species that is adapted to live in the sunlight zone. Explain one adaptation of fish species in the sunlight zone. … … … … [2] [Total: 17]

17 marks

Mark scheme: 2(a) any 3 of: release net into sea / release net from boat / AW ; boat circles round (so net surrounds) fish / surround the fish with the net / AW ; drawstring / ropes, pulled to, close net / close bottom of net / AW ; ref. to net (with catch) pulled on board boat ; 2(b)(i) large drawing ; neat, clear lines that are not broken lines and no shading ; (proportions of all correct) width of tail is more than width of body ; operculum, pectoral fin, caudal fin, eye, and mouth present in correct locations ; 4 2(b)(ii) name: caudal (fin) ; function: thrust / move fish forward / drives it forward / AW ; 2 2(b)(iii) 16 (cm) ;; OR correct measure of length of line X ; division of length by 0.85 ; 2 2(b)(iv) domain (Eukarya) + (kingdom) animals (genus) Scomber + (species) scombrus 2 Question Answer Marks 2(c)(i) any 2 of: light / sunlight ; high oxygen (concentration) / AW ; low pressure ; variation in temperature / variable temperature / AW ; 2 2(c)(ii) Any 2 of: counter-shading / camouflage / AW ; escape from predators / catch prey / AW ; OR fast swimmers / streamlined / AW ; escape from predators (as there is no shelter) / catch prey ; OR generalist feeding / can eat many different types of food / AW ; due to competition / availability of food / AW ; OR migratory ; to reach breeding / feeding grounds / AW ; 2

This question in 0697/23 May/June 2024