ZOO 302: BIODIVERSITY &

CONSERVATION (3 UNITS)




INTRODUCTION

Dr. David Wechuli, PhD

Lecturer, Department of Biological Sciences
University of Kabianga
1
 Course Outline
 Introduction and concepts on biodiversity

and conservation;
 Types, levels, values, nature and function of
biological diversity;
 Threats to biodiversity and consequences of
biodiversity loss.
 Principles of conservation & endangered
animals of Kenya. 2
 Genetic material collection, preservation,
conservation and the role of gene banks.
 Conventions on biodiversity.
 Conservation strategies and policies.
 Role of organizations in the conservation
of Biodiversity.
 Emerging issues and trends

3
Course evaluation
a

S/No. Mode of evaluation Marks %

1 CAT (1) 20

2 Assignments (1) 10 10

3 Practical (1) 10

4 EXAMS 70

Total Score 100

4
References
1. Esa Ranta, Per Lundberg and Veijo Kaitala.Published: (2005).

Ecology of Populations

2. Malcolm L. Hunter 1999. Maintaining Biodiversity in Forest

Ecosystems.$101.00 (Z)J. Ward Thomas, M. Hunter, R. Seymour,

B. Palik, T. Spies, A. Hansen, J. Rotella, G. Matlack, Y. Haila, M.

Brinson, J. Verhoeven, A. Calhoun, W. McComb, D. Lindenmayer,

N. Brokaw, R. Lent, S. Moore, H. Lee Allen, I. Thompson, P.

Angelstam, C. Millar, L. Frelich, K. Puettman, D. Norton, C. Oliver,

M. Boyda, G. Segura, B. Bare, B. Lippke, J. Bishop, L. Maguir

5
References
3. Trevor R. Hodkinson, Michael B. Jones and Stephen
Waldren.Published: June 2011 Climate Change,
Ecology and Systematics.
4. R. J. Berry, T. J. Crawford and G. M. Hewitt.Published:
August 199.Genes in Ecology: 33rd Symposium of the
British Ecological Society.
5. D Tilman, PM Kareiva - 1997 [BOOK][B] Spatial
ecology: the role of space in population dynamics
and interspecific interactions.
6
References
6. F Schwerdtfeger - 1979 [BOOK][B] Animal
ecology. A text-and handbook in three parts.
Volume II: demecology. Structure and
dynamics of animal populations.
7. Charles Perrings, Karl-Goran Maler and Carl
Folke. Published: January 1997. Biodiversity
Loss: Economic and Ecological Issues

7
 Biodiversity
 Defined: The range of organisms present in a
particular ecological community or system.

 Biological diversity that means the richness and

variety of life on Earth,
e.g., animals, plants and micro-organisms plus the
genes they contain and the complex ecosystems
they help form.
8
 The variety of species and ecosystems on
Earth and the ecological processes of
w h i c h t h ey a re a p a r t – i n c l u d i n g
ecosystem, species, and genetic diversity
components.

9
 The variability among living organisms
from all sources including, inter alia
(among other things), terrestrial, marine
and other aquatic ecosystems and the
ecological complexes of which they are
part; this includes diversity within species
, between species and of ecosystems

10
 The variability among living organisms
from all sources including, inter alia,
terrestrial, marine and other aquatic
ecosystems and the ecological complexes of
which they are part; this includes biological
diversity within species and ecosystems.
 Total diversity & variability of living
organisms & of the systems which they’re a 11
 Biodiversity-not the same as nature,
wildlife, natural capital or other commonly
used terms.
 But it supports and enhances all of these
other aspects of the natural world, and/or
reduces the risks to them.
 Other terms used interchangeably with
biodiversity- not quite the same thing
12
Terms used interchangeably with biodiversity but
which does not mean the same

13
Terms used interchangeably with biodiversity but
which does not mean the same

14
 Ecological diversity
 Is the available biological diversity within an
ecosystem. It looks at variety of ecosystems
within which life exists They include:
• Forests ecosystems
• Arid and semi arid ecosystems
• Aquatic ecosystems

15
• Fresh water ecosystems
• Marine ecosystems
• Wetland ecosystem
• Grassland ecosystems

16
 Types of Biodiversity

Three types (diversity indices) of

biodiversity;
i. Alpha (α ) Diversity:

Species diversity within a community or

habitat.

Comprises two components i.e.

17
ii) Beta (β) Diversity:

Inter community diversity expressing the

rate of species turnover per unit change in

habitat.

iii) Gamma (γ) Diversity:

Overall diversity at landscape level and

18
The types of Biodiversity is best represented
using the relationship:

γ=α+β+Q
where,
•Q = Total number of habitats or
communities,
•α = Average value of α diversities 19





Levels of Biodiversity
Theoretically there are three levels of
biodiversity
 Genetic,
 Species,
 Ecosystem

20
 Genetic Diversity
 The sum of all the different genes

contained in all individual plants, animals,

fungi, and microorganisms.

 Occurs within a species & between species.

 Any variation in the nucleotides, genes,

chromosomes, or whole genomes of

organisms.
21
 The sum total of genetic information,
contained in genes- plants, animals &
microorganisms
 Role-to maintain reproductive vitality,
resistance to disease & ability to adapt to
changing conditions.
 Enables a population to adapt to its
environment and to respond to natural
22

selection.
 The amount of genetic variation is the basis
of speciation.
 Genetic diversity within a species often
increases with environmental variability.
 Hence made it possible to produce new
breeds to adapt to changing conditions.

23
 Measured in terms of the total number of
s p eci es wi thi n di s crete geo gra p hi ca l
boundaries.

 Species diversity is looked at under;

1. Species Richness
2. Species (Evenness) Abundance
3. Taxonomic or phylogenetic diversity
24
 Species Richness - Refers to the total
count/number of species in a defined
area.
 Species (Evenness) Abundance - Refers to
the relative numbers among species.
 Taxonomic or phylogenetic diversity –
-Genetic relationships btn the diff groups
of sp
25

-Hierarchical classification- phylogenetic

Low species diversity suggests:
•Relatively few successful sp live in the
habitat
•The environment is quite stressful with
relatively few ecological niches-well adapted
to that environment
•Relatively simple food webs are present
•Change in environment- quite serious
26
High species diversity suggests:
•A greater number of successful species
and a more stable ecosystem
•More ecological niches-environment is less
likely to be hostile
•Complex food webs
•Environmental change is less likely to be
damaging to the ecosystem as a whole
27
 What is a Species?
 The concept of a species is fundamental
to biology, yet biologists disagree on exactly
what constitutes a species.
 There are several different, working
definitions of a “species”

28
“Biological Species Concept”
 “A species is a group of actually or
potentially interbreeding organisms that
can mate and produce fertile offspring” –
Ernst Mayer

 This definition is very interesting from an

evolutionary perspective. It defines species
as “real”, objective entities, defined by the
limits of gene exchange
29
“Morphological Species Concept”
 “Species are Groups of Organisms that
Share Certain Morphological or Biochemical
Traits”

 Some species do not reproduce sexually,

some are known only from fossils. This
definition is the working definition used by
biologists that cannot, or should not, use
the “Biological Species Concept”
 It is more subjective 30
“Phylogenetic Species Concept”
 A s p ec i es i s a d i s c r et e l i n ea g e,
propagated, ancestor to descendent
through time, which is recognizably
different from other such lineages
and shares a distinct evolutionary
history.

 It defines a species by its relationship

to other species. 31
Population-
A group of organisms of one species living in
the same place at the same time that
interbreed and compete with each other for
resources (ex. food, mates, shelter)

32
33
 Ecosystem Diversity
Dif f . ha bita ts, Bio l c o mmunities, ec o lo g ic a l
p ro c esses, a nd va ria tio ns w ithin individu a l
ecosystems.
Levels and scales:
Functional diversity: The relative abundance of
functionally different kinds of organisms
Community diversity: The number, size and spatial
distribution of communities-patchiness
Landscape diversity: The diversity of scales of 34
Spatial scale terms
1.Alpha Diversity -diversity within a particular area
or ecosystem, and is usually expressed by the
number of species in that ecosystem.
2.Beta diversity : a comparison of diversity between
ecosystems, measured as the amount of species
change between the ecosystems .
3.Gamma diversity : a measure of the overall
diversity within a large region. 35
Community-Level Diversity

36
 Biodiversity Principles
Are based on the following 8 items
Go native - Native areas (wetlands, aquatic
areas, riparian areas, forests/woodlands, and
grasslands)
Semi-natural -(e.g., shelterbelts, hedgerows,
pastures and haylands, buffers, road margins)
Location - The location, pattern, and seasonal
availability of habitat influences the type and
amount of biodiversity present.
 Connection - Connecting native and semi-
natural areas of land with neighbouring
landscapes
 Achieving structural diversity- The
variation in physical structure of both
native vegetation and crops
 Healthy ecosystems - The health of native
and semi-natural areas, farmland, soil
38

and water
 Variety - The number and mix of species
present, including crops and livestock

 Aliens - Invasive alien species are

generally detrimental to the conservation
of biodiversity.

39