Biodiversity Research in Cape Verde WatersReinhold Hanel & Sónia Merino

LocationBoundary Layer for distribution of tropical African spec ies

High Rate of Endemism

The biogeographic significance of theCape Verde archipelago

Florida

Cape Verde Islands

Madeira

Azores

Canary Is.

Biogeographic Mixing ZoneGaotfish diversity in Cape Verde

Pseudupeneus preyensis

Mullus barbatus

Mullus surmuletus

Mulloidichthys martinicus

Madeira

Azores

Canary Is.

Florida

Bolten et al., 1998

Cape Verde Is.

The transatlantic migration hypothesis for loggerhead sea turtles

Cape Verde as a refugee area during glacialperiods

The Cape Verde Archepelago

What roles do Cape Verdean seamounts and oceanic islands play in the biogeography, biodiversity, productivity, and evolution of marine organisms of the Central Eastern

Atlantic?

Biogeographic comparisons on plankton and micronekton communities

The Galathea Sargasso Sea Expedition –March, April 2007

• What factors drive seamount and oceanic island community structure , diversity, productivity, and endemism, both at the scale of whole seamounts and individual habitats within seamounts?

• What are the key processes influencing the differences in communities observed between seamount and non-seamount regions, and among seamounts?

• What are the impacts of exploitation (fisheries, mining) on seamount and island community structure and function?

Major Issues

Sampling locations during Poseidon cruise in April 2005:

(a) south of Brava/Fogo;(b) southwest of Boavista; (c) at Senghor Seamount/Nova Holanda Bank

a

b

c

Sal

SenghorSeamount

Sampling transect over the Senghor Seamount duringPoseidon cruise in April 2005

Fish larvae sampled during Poseidon cruise 320/2 at Cape Verde Islands in April 2005

Identification of 90 fish species

First description of early developmental stages of Capeverdean demersal species

Chromis lubbockiChromis cyanea

Xenophthalmichthys danaeHimantholophus cornifer

Mesopelagic fish sampled during Poseidon cruise320/2 at Cape Verde Islands in April 2005

Worldwide extremely rare and biologically almostunknown species

Cephalopods sampled during Poseidon cruise 320/2 at Cape Verde Islands in April 2005; separated by sampling locations and gears.

Sepia officinalis

Octopus vulgaris

Ommastrephes bartrami

Abraliopsis atlanticaJapetella diaphana Onychoteuthis banksi Cranchia scabra

Investigations on food web interactions based on stable isotope analyses (d13C, 15N)to elucidate trophodynamic interactions

April 2005

δδδδ13C (‰)

-22,5 -22,0 -21,5 -21,0 -20,5 -20,0 -19,5 -19,0

δδ δδ15N

(‰

)

3,03,54,04,55,05,56,06,57,07,58,08,59,0

Calanoid copepod (type 1)

Calanoid copepod (type 1)

Calanoid copepod (type 2)

Euphausia (type 4)

Euphausia (type 4)

Euphausia (type 7)

Flaccisagitta (type 10)

Flaccisagitta (type 10)

Sagitta (type 11)

Salpa (type 6)

Why could it be useful?

Application for fisheries managementpurposes

Major Families of Prey Fish

0

20

40

60

80

100

Mycto

phida

e

Percic

hthyid

ae

Chiasmodo

ntida

e

Gonos

tomat

idae

Gempy

lidae

Scopela

rchid

ae

Scombr

olabra

cidae

Parala

pedid

ae

Tetra

gonur

idae

Ostra

ciida

e

Exoco

etida

e

Balist

idae

Chaeto

dontid

ae

Acanth

uridae

Bramidae

% o

f sam

ples

Bigeye Yellowfin

Cross Seamount Tuna: Frequency of Occurrence of Pre y Fish Families

epipelagicsmesopelagics

Holland et al. 2000

Major Taxa of Invertebrate Prey

0

20

40

60

80

100

Cephalo

poda

Serge

stida

e

Oploph

orida

e

Penae

idae

Pandali

dae

Isopod

a

Enople

metoph

idae

Eupha

usiac

ea

Amphipoda

Stomat

opoda

Megalo

pae

% o

f sam

ples

Bigeye Yellowfin

Cross Seamount Tuna: Frequency of Occurrence of Inv ertebrate Prey

epipelagicsmesopelagics

Holland et al. 2000