Fischdiversität limnischer und mariner Ökosysteme

Rainer FroeseIFM-GEOMAR, Kiel

rfroese@ifm-geomar.de8. Tagung GFI, Frankfurt, 2.9.2011

Phylogeny of Fishes(based on FishBase 08/2011)

In Kingdom Animalia, Phylum Chordata, Fishes comprise• 6 Classes• 64 Orders• 537 Families• 4,955 Genera•31,857 Species

Phylogeny of FishesClasses Common

ancestor(million y)

Orders(n)

Families(n)

Genera(n)

Species(n, %)

Myxini (hagfishes) 600 1 1 6 78 0.2

Cephalaspidomorphi (lampreys)

450 1 1 8 43 0.1

Holocephali (chimaeras) 420 1 3 6 50 0.1

Elasmobranchii (sharks and rays)

420 11 50 187 1,137 3.6

Sarcopterygii (lobe-finned fishes)

420 3 4 4 8 0.04

Actinopterygii (ray-finned fishes)

400 47 478 4,743 30,541 95.9

Total 64 537 4,954 31,857 100

FishBase 08/2011

Fishes by Salinity

• Primary freshwater fishes 14,349• Primary marine fishes 14,786• Brackish & diadromous fishes 2,976

Based on FishBase 08/2011Counts include subspecies

Human Use of Fishes

Extant finfish 32,111•Used in fisheries 4,662•Used in aquaculture 364•Used as bait 205•In ornamental trade 3,233

– marine 1,327– freshwater 1,906– mainly bred 702

•Used in angling 1,139 Total used by humans 7,398

Based on FishBase 08/2011Counts include subspecies

Fishes Affected by Humans

• Threatened by extinction 1,737– (Based on IUCN Red List of 2010)

• Introduced between countries 877– (transferred to and establish in another country)

Based on FishBase 08/2011Counts include subspecies

Fishes Affecting Humans

• Dangerous fish 1,038– (poisonous, venemous, traumatogenic, pests, etc.)

Based on FishBase 08/2011Counts include subspecies

How To Get There

• www.fishbase.org• Section ‚Tools‘• Button ‚Fish Statistics‘

10

Size Distribution of Fishes

0

500

1000

1500

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5

Length (log; cm)

Fre

qu

en

cy

Frequency distribution of maximum lengths in 23,685 species of fishes, Median = 15.9 cm

11

Extreme Size in Fishes

• What are the largest fishes on Earth?– FishBase, Tools, World Records

• 10 largest fishes

• What are the smallest fishes on Earth?– FishBase, Tools, World Records

• 10 smallest fishes

12

Why Does Size Matter?Some Things Increase!

• Predators are larger than their prey• FB, FishBase Book, Trophic Ecology, The Predators Table

• Swimming speed increases with body length• FB, FishBase Book, Morphology and Physiology, The Swimming

and Speed Tables

• Fecundity increases with size (Fec = aLb)– b median = 3

• FB, Coryphaena hippurus, More information, Spawning, USA - Florida current, a = 0.252, b = 3.12

• References increase with size

13

Why Does Size Matter?Some Things Decrease!

• Metabolic rate decreases with size• FB, Oreochromis niloticus, More information, Metabolism, Relative oxygen

consumption graph

• Growth rate decreases with size• FB, O. niloticus, More information, Growth, Auximetric graph

• Natural mortality decreases with size• FB, O. niloticus, More information, Growth, M vs. Linf graph

• Relative brain size decreases with size• FB, O. niloticus, More information, Brains, Relative brain weight graph

• Relative gill area decreases with size• FB, O. niloticus, More information, Gill area, Gill area vs body weight

graph, About this graph

14

Why Does Size Matter?Some Things Don’t Change (Much)

• Size at maturity• FB, Oreochromis niloticus, More information, Growth,

Reproductive load graph

• Body proportions• FB, O. niloticus, More information, L-L relationship, e.g.

SL = a + b TLif a = 0 then SL is a fixed ratio of TL

• FB, O. niloticus, More information, L-W relationship: -> if b ~ 3 then isometric growth

Most Fish Grow Isometrically

0

100

200

300

2.0 2.5 3.0 3.5 4.0

b

Fre

qu

en

cy (

n)

Frequency distribution of mean exponent b based on 3,929 records for 1,773 species, with median = 3.025, 95% CL = 3.011 – 3.036, 5th percentile = 2.65 and 95th percentile = 3.39, minimum = 1.96, maximum = 3.94; the normal distribution line is overlaid.

W = a Lb

Fish Grow Forever

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 1 2 3 4 5 6

Age (in units of mean adult life expectancy)

We

igh

t (r

ela

tiv

e t

o m

ax

imu

m w

eig

ht)

Fishes Bivalve Euphausiid Trees Newt Squid

Whale shark vs Fin whale

0

500

1000

1500

2000

2500

0 10 20 30 40 50 60

Age (years)

Len

gth

(cm

)

Fin whale

Whale shark

Maturity is Size-Driven

• Growth in weight has an inflection point at 0.3 Winf = 2/3 Linf (if growth is isometric with b ~ 3)

• Fish mature before or at that size

0

2000

4000

6000

8000

10000

12000

14000

16000

0 5 10 15 20

Age (years)

Wei

gh

t (g

)

max dW/dt

First maturity

Variability in Maturity

1

10

100

1000

10000

1 10 100 1000 10000

L∞ (cm)

Lm

(cm

)

L∞

0.67 L∞

0.35 L∞

Longevity vs Taylor’s 3/K

353 species, FishBase 11/2006

0.1

1

10

100

1000

0.1 1 10 100 1000

Age at 95% L∞ (years)

Ob

serv

ed m

axim

um

ag

e (y

ears

)

1 : 1

Longevity vs Temperature

y = -0.0142x + 1.3505

R2 = 0.0702

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

0 5 10 15 20 25 30

Mean annual temperature (degree Celsius)

Ob

serv

ed lo

ng

evit

y (l

og

; ye

ars)

Longevity vs Maximum Length

0.1

1

10

100

1000

1 10 100 1000

Maximum length (cm)

Max

imu

m a

ge

(yea

rs)

Maximum age and length known for 1036 species of fishes, FishBase 11/2006

Maximum Length vs Longevity

1

10

100

1000

0.1 1 10 100 1000

Maximum age (years)

Max

imu

m l

eng

th (

cm)

Maximum length and age known for 1036 species of fishes, FishBase 11/2006(Slope = 0.80, 95% CL = 0.76-0.84, r2 = 0.6124)

L∞ vs tmax within Species

1

10

100

1000

10000

0.1 1 10 100 1000

Age at 95% L∞ (years)

Asy

mp

toti

c le

ng

th (

L∞ ;

cm

)

Carcharhinus acronotus Pleuronectes platessa Stolephorus indicus

Median slope for populations within 141 species = 0.42 (95% CL = 0.39-0.46)

6410 growth studiesFishBase 11/2006

Longevity vs Age at Maturity

y = x + 0.61

R2 = 0.674

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

-0.5 0.0 0.5 1.0 1.5

Age at maturity (log; years)

Ob

se

rve

d lo

ng

ev

ity

(lo

g;

ye

ars

)

tmax ~ 4 * tm

Longevity vs Environment

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

Freshwater  Brackish  Marine

Environment

Lo

ng

ev

ity

(lo

g;

ye

ar)

Diadromous

Longevity vs Habitat

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

Deep Demersal Pelagic Reef

Habitat

Lo

ng

ev

ity

(lo

g;

ye

ar)

Natural Mortality is Rather Constant in Adults

0

200

400

600

800

1000

1200

0 5 10 15 20 25

Cohort age (years)

Co

ho

rt n

um

ber

s

Nt = Nts * exp(-M*(t - ts))

Life History Summary

Note: Blue line is not to scale

Growth in Weight

0

2

4

6

8

10

12

14

16

18

0 5 10 15 20 25

Age (years)

Weig

ht

(kg

)

maturity

max growth

max reproductive biomass

asymptotic weight

Gadus morhua , Linf = 120 cm,K = 0.14, M = 0.2, rel Fec = 20%

average adult lifespan

max age

Six Zoogeographic Realms

Alfred Russell Wallace, 1876. The Geographical Distribution of Animals

Freshwater Fish Diversity

Realm Species•Nearctic 1,096•Palearctic 1,438•Neotropical 4,388•Ethiopian 3,215•Oriental 2,843•Australian 674

Based on FishBase 08/2011Counts include subspecies

Global Species Richnesswww.aquamaps.org

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0

500

1000

1500

2000

2500

40 80 120 160 200 240 280

Longitude (degrees)

Nu

mb

er

of

sp

ec

ies

(n

)

Maldives

Galapagos

Marshall I. Howland/Baker

Sumatra

Borneo

Celebes/Halmahera

Somalia

Ecuador

Seamount

Tools:Equatorial Species Richness Transect across the Indo-Pacific

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Fish Diversity of the Oceans

Arctic 130

Atlantic4,900

Pacific10,500Indian

6,000

Pacific10,500

Antarctic 370

Total: ~16,000 marine or diadromous fishes, several thousand in more than one Ocean

Diversity in Large Marine Ecosystems

North Sea190

Mediterranean700

Caribbean1,600

Canary1,300

South Brazil970

Patagonian340

Benguela820

Greenland190

Humboldt750

California800

Alaska320

Hawaiian840

Red Sea1,200

Agulhas1,400

Bay of Bengal700

West470

Indonesian2,400

East1240

Australian

East-China1,040

Polynesian810

Weddell Sea25

How About Climate Change?

37

Expected Changes in Environmental Parameters in 2050

Climate zone Surface Temp. (°C)

BottomTemp. (°C)

Salinity BottomSalinity

Ice concentration (%)

Arctic +0.7 +1.6 -1.2 -0.8 -9

Temperate N +0.4 +0.8 -0.7 -0.3 -2

Subtropical N +1.0 -0.1 -0.3 -0.0 0

Tropical +1.4 -0.3 -0.2 0.0 0

Subtropical S +0.5 +0.3 -0.2 0 0

Temperate S +0.4 +0.7 -0.1 0.0 -0.3

Antarctic +0.7 +0.5 -0.2 0.0 -3

38

Preliminary Analysis

• 821 marine fishes with verified maps• Global suitable habitat in 1999 and 2050• Only core habitat considered (P > 0.5)

39

More Losers than Winners

Change in suitable habitat area in 2050 for 821 species of marine fishes. Median loss in area is 6% (95% CL 5.1 – 6.8), significantly different from zero.Data from AquaMaps 2010.

Sharks and Bony Fish Lose Both

Change in suitable habitat area in 2050 by Class. No loss for 2 lampreys and 3 chimaeras. About 6 % loss for 128 sharks and rays and 688 ray-finned fishes. The areas that are most suitable for sharks and rays do not shrink or expand more than those for ray-finned fishes.Data from AquaMaps and FishBase.

Evolution Did Not Help

Change in suitable habitat area in 2050 by phylogenetic rank, with primitive species on the left and highly derive species on the right. The areas most suitable for primitive species do not shrink or expand more that those most suitable for highly-derived species.

Being Special Does Not Help

Change in suitable habitat area in 2050 by phylogenetic uniqueness of the respective species, for 821 marine fishes. The areas most suitable for unique species do not shrink or expand more than the areas most suitable for species with many close relatives.

Size Does Not Matter

Change in suitable habitat area in 2050 by maximum body length for 821 marine fishes. The areas most suitable for large fishes do not shrink or expand more than those of small fishes.

Highways and Homes

Change in suitable habitat area in 2050 by migratory behavior for 821 marine fishes. The areas most suitable for oceanodromous and diadromous fishes do not lose or gain more than those of non-migratory fishes.

No Change (yet) in the Deep(but reefs are getting hot)

Change in suitable area in 2050 by preferred habitat for 821 marine fishes. The deep sea and its (104) species are less affected by climate change. More than 50% of the reef-associated fishes are likely to lose suitable habitat.

The Tropics Lose

Change in suitable area in 2050 by climate zone for 821 marine fishes. Deep-sea areas (113 species) show no significant change. Also, suitable polar areas (19 species) show no change, maybe because losses due to increased temperature are made up for by receding ice-cover. Temperate species (128) may gain slightly (Median 1.6%, 95% CL -0.4 – 3.1). Suitable areas for subtropical (227) and tropical (334) fishes shrink significantly by about 8%.

Cosmopolitans Less Affected (1)?

Change in suitable area in 2050 by size of current suitable area, for 821 marine fishes. Extreme points may be artifacts. Overall it seems that suitable areas of 0.5 to 20 million km2 have more potential for shrinkage than areas over 40 million km2.

Cosmopolitans Less Affected (2)?

Change in suitable area in 2050 by latitudinal range, for 821 marine fishes. No trend is visible.

Summary

• Fishes are the largest group of vertebrates• Fishes are well researched• Eschmeyer‘s Catalogue of Fishes and Fishbase

are unique resources of standardized information

• Fishes are well suited for studies in macro-ecology and global biodiversity

Thank You

Rainer FroeseIFM-GEOMAR

rfroese@ifm-geomar.de