Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Fisheries Monitoring and Assessment > Mackerel Biology and Fishery > Flashcards

Mackerel Biology and Fishery Flashcards

(81 cards)

Start Studying
1
Q

What class does mackerel belong to?

A

Actinopterygii

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What order does mackerel belong to?

A

Perciformes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What family does mackerel belong to?

A

Scombridae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the scientific name for mackerel?

A

Scomber scombus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the Irish mackerel fishery

A

-Exploited in a directed fishery for human consumption
-Single most important fishery
-Numerous jobs as sea and on coast
-Largest and most economically valuable pelagic stock in NE Atlantic
-Processing industry depends on landings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where is the main port?

A

Killibegs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where also is mackerel landed?

A

Norway and UK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What export markets are there for mackerel?

A

Germany, Russia, Egypt and Africa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What ways are mackerel sold?

A

-Fresh
-Frozen
-Smoked
-Canned

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What ways are mackerel sold?

A

-Fresh
-Frozen
-Smoked
-Canned

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How are mackerel fished?

A

Modern pelagic trawls
Mid water otterboard trawling
Purse Seining

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the main fishing season for mackerel?

A

October to March

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When is the Irish mackerel fished?

A

January / February

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What habitats are mackerel caught in?

A

Shelf areas and along the shelf edge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What depths are mackerel caught at?

A

15 - 200 m

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What type of fish are mackerel?

A

Pelagic, but can be found anywhere in the water column
-Typically epipelagic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Are mackerel solitary or shaoling?

A

Shoaling, with shoals 9km long, 4km wide and 40m deep

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where are mackerel commonly found?

A

Cold and temperate shelf areas (>6 degrees)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where are mackerel commonly found?

A

Cold and temperate shelf areas (>6 degrees)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Do mackerel have a swim bladder?

A

No, they must constantly swim or they will sink

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe mackerel.

A

-Metallic blue-green dorsally
-Fade to silver along sides and belly
-20-30 wavy black bars running down sides
-Atlantic mackerel have tapered body, large head and mouth
-Two large dorsal fins and forked caudal fin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

The is the maximum length of mackerel?

A

66cm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the average length of mackerel?

A

40-44 cm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the max recorded weight?

A

3.3 kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the average weight of mackerel?
0.68 kg
26
How can mackerel age be determined?
Otoliths- unreliable after 6-7 years of age Scales- unreliable
27
Do juvenile mackerel grow quickly?
Yes
28
What size can mackerel be after 1 year?
22 cm
29
What size can mackerel be after two years?
30 cm
30
What is the minimum landing size of mackerel?
30 cm
31
What is size range of catches?
33-35 cm This can vary with year/location (20-40cm)
32
What is the age catch range of mackerel?
1- 15 years
33
What is the average catch age for mackerel?
4-8 years
34
When are mackerel sexually mature?
2-4 years
35
How many female mackerel spawn at two years old?
60%
36
What is the NEA?
Northeast Atlantic mackerel and is assessed as one stock
37
What are the three spawning components of the NEA mackerel stock?
Western Component - 77% of NEA Southern Component - 19% of NEA North Sea Component- 4% of NEA
38
What divisions are included in the Western component?
VI, VII, VIIIa,b,d,e
39
What divisions make up the southern componenet?
VIIIc, IXa
40
What divisions make up the North Sea component?
IV, IIIa
41
What is the total distance that mackerel will travel in a year?
500 - 1000 nautical miles
42
Do juveniles travel as far north as adults?
Tagging has shown that juveniles do not migrate as far north
43
How fast can mackerel swim?
5.5 meters / sec and up to 50 nautical miles a day
44
Where are the mackerel feeding areas?
June - January West Scotland- Shetland islands Norwegian sea North sea
45
Are mackerel migratory?
Highly
46
Where do mackerel overwinter?
December to February North of Scotland
47
Where are mackerel spawning grounds?
February - July South, South west of Ireland
48
Where do mackerel that spawn in southern and western areas migrate to feed?
To Nordic seas and North sea during second half of year after spawning
49
What does the path of the migration coincide with?
With the location of the relatively warm high saline eastern Atlantic water flowing northeastwards
50
What has been linked with timing of overwintering, spawning migration?
Linked with temperature -earlier overwintering and spawning related to increased temperatures
51
Why is it thought that extended migrations to Iceland have been happening?
Thought to be due to climate change
52
What depths do mackerel spawn at?
Continental shelf, in shallow waters (200m)
53
What temperatures do mackerel spawn at?
Between 9 - 10 degrees
54
Describe mackerel early spawners
-Winter slopes near spawning area -March/April -Larger and older fish
55
Describe mackerel late spawners
-Winter further away -Spawn May/ July -Smaller and younger fish -First time spawners
56
What type of spawners are mackerel?
-Batch spawners, eggs are laid in batches over a period of time
57
How many batches are laid?
20 separate
58
How many eggs can female mackerel lay?
400,000 - 500,000 Average 250,000
59
What size is mackerel eggs?
1.2 mm
60
How long does it take for mackerel eggs to hatch?
5 - 10 days
61
What size are mackerel larvae with yolk sacs?
2.5 mm
62
How long does it take for larvae to absorb their egg yolks?
9 days
63
What do mackerel feed on?
-Plankton -sand eels -Sprat -Norway pout -Polychaetes -Zooplankton -Crustacea
64
What do larvae feed on?
Copepods
65
Do mackerel feed during the winter?
They stop feeding almost completely during winter
66
Describe pelagic trawlers
Up to 100m, operate individually or in pairs
67
How do freezers trawlers operate?
Up to 150m and use mid water pelagic nets
68
What does RSW stand for?
Refrigerated Sea Water
69
What depths to purse seiners operate at to catch mackerel?
>20 m
70
What do Norwegians fish?
Mackerel at the overwintering grounds close to shore
71
Who uses gill nets?
Spain and Norway
72
Who uses lines and jigs?
Norway and the UK
73
Who tends to pair trawl?
Ireland and Faroe islands
74
Where is traditionally the highest catches of mackerel being caught?
North Sea around the Shetland islands, west coast of Scotland and Ireland
75
Where is recent years is there high catches of mackerel?
in Icelandic and Faroese waters , where there was no reports of catches prior to 2006
76
In 2013, how much of the total reported landings were in Iceland?
Almost half
77
When was mackerel catches reported for the first time in Greenland?
2011
78
What was the EU TAC quota for mackerel in 2021?
119,573 tonnes
79
What was the Irish mackerel quota in 2021?
60,847 tonnes
80
When can Irish fishermen fish for mackerel in regards of the quota?
80
When can Irish fishermen fish for mackerel in regards of the quota?
Can be fished in UK waters 4.a during periods of: -1st Jan -14th Feb -1st Aug - 31st Dec (2021)

Fisheries Monitoring and Assessment (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions