Aquaculture continues to significantly expand its production, making it the fastest-growing food production sector globally. However, the sustainability of the sector is at stake due to the predicted effects of climate change that are not only a future but also a present reality. In this Lecture, we review the potential effects of climate change on aquaculture production and its implications on the sector ’ s sustainability. Various elements of a changing climate, such as rising temperatures, sea-level rise, diseases and harmful algal blooms, changes in rainfall patterns, the uncertainty of external inputs supplies, changes in sea surface salinity, and severe climatic events have been discussed. Furthermore, several adaptation options have been presented as well as some gaps in existing knowledge that require further investigations.

1. Impact of Climate change on fish
Production
Dr. Abd El Rahman Khattaby
‫د‬
.
‫خطابى‬ ‫أحمد‬ ‫عبدالرحمن‬
Technical Support Manager at Aller Aqua Egypt
Senior Researcher at Central Laboratory for Aquaculture Research, ARC, Egypt
+201009016959 | a.a.khattaby@gmail.com | WhatsApp: +201009016959

2. Climatechangeis oneof thechallengesfacingfisheries
Aquaculture continues to significantly expand its production, making it the
fastest-growing food production sector globally.
However, the sustainability of the sector is at stake due to the predicted effects
of climate change that are not only a future but also a present reality.
In this Lecture, we review the potential effects of climate change on
aquaculture production and its implications on the sector’s sustainability.
Various elements of a changing climate, such as rising temperatures, sea-level
rise, diseases and harmful algal blooms, changes in rainfall patterns, the
uncertainty of external inputs supplies, changes in sea surface salinity, and
severe climatic events have been discussed. Furthermore, several adaptation
options have been presented as well as some gaps in existing knowledge that
require further investigations.

3. ClimateChanges
Climate changes are a result of the various
burning processes of oil, gas, wood and coal.
It is accompanied by huge amounts of toxic
chemical compounds to the atmosphere, the most
important of which are carbon oxides, sulfur and
nitrogen,.

4. ClimateChanges
and these gases are considered as a heavy gases that remain in the lower range
of the Earth and prevent the spread of heat as they absorb infrared radiation,
which leads to an increase in temperature in a called "global warming", Climate
change are dangerous due to pollution of air, water and soil, and the destroy
ecosystems
CO2
CO2
CO2
CO2
CO2
CO2
CO2

5. Whyistheclimatechanging?
Adapted
from
https://thewellesleynews.com/ CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
The release of carbon dioxide and other greenhouse gases
traps the sun's heat in Earth's atmosphere
©FAO/Abhichon
Rattanabhayon
©Hazel
Oxenford
©FAO/Graeme
Maclean

6. Impactof Climatechangeon watersystems
*Climate change affects rainfall patterns and melting
snow and ice, and affects water resources in terms of
quantity and quality
*Rainfall pattern mean several changes ranging from
drought and shortages to floods and poor water quality.
*The salinization of groundwater and its movement in the
direction of the upper rivers due to the rise in sea level
will threaten the aquatic life in the inland fresh water.
* Higher temperatures will reduce dissolved oxygen
levels and increase fish metabolic rates, leading to
increased fish mortality, while increasing the spread of
diseases.

7. Implicationsof climaticchangesonwatersystems(water
temperature)
* The warming of the atmosphere and
oceans is due to the increase in the
concentration of carbon dioxide and
greenhouse gases in the atmosphere.
* The warming of the oceans, especially
in the tropics, subtropics.
* An increase in the water temperature of
surface fresh water.
What are the main pressures of
climate change?
tornados
powerful
Ocean acidification
changes in ocean
currents
Severe weather

8. Implicationsof climaticchangesonwatersystems
(oxygencontent)
❑Dissolved oxygen is an important component of aquatic systems,
and change in its concentration has significant effects on carbon
and nitrogen.
❑CO2 concentrations increased by 40% of fuel emissions.
❑Dissolved oxygen levels decrease with increasing temperature in
both coastal and marine areas.
❑Decreased oxygen in the water column reduces vertical migration
depths for some species (ex. tuna and fish) and reduce the
distribution of fisheries species.
Whatdoesloweroxygen
levelinwatermean?

9. Whatdoesloweroxygen
levelinwatermean?
• death of fish
• Expansion of the "dead
zones"
• slower growth
d
r
o
f
e
n
x
O
el
az
H
©FAO/Carla
Daniel
• Less living space for pelagic
fish species such as tuna
©adapted
by
CERMES

10. Implicationsof climaticchangeson
watersystems(IceCover)
❑The rise in temperature led to the melting of part of the ice in the
Arctic by about one million square kilometres, which led to a rise in
sea and ocean levels, which in turn caused the flooding of most of
the islands, river deltas and coastal areas, which include agricultural
lands and areas full of people.
❑Melting snow and snow cover and reducing mountain glaciers
contribute to rising water levels and flows into aquatic systems.
❑Sea level rise is a direct result of melting ice, while reducing
mountain glaciers will have an impact on river flow and lake levels.

11. Implicationsof climaticchangesonwater
systems(Watersurfacelevel)
❑The sea level is rising at an average rate of 3.1 mm/year as a
result of climatic and non-climatic factors.
❑Sea level has already risen by a global average of 0.19 meters
over the period from 1901 to 2010.
❑It is estimated that between 2000 and 2100, the projected average
sea level rise will be between 0.5-1.2 metres.
❑The sea level is expected to rise 95% of the ocean area level.
Whathappenswhen
sea​​levelrises?

12. Whathappenswhen
sea​​levelrises?
❑coastal erosion
and More flooding with huge storms
❑Damage to critical fish habitats (mangroves)
❑Destruction of coastal areas and aquaculture ponds
©Shelly-Ann
Cox
©Hazel
Oxenford
©Hazel
Oxenford

13. Harmfulalgalblooms
Increased frequency of warmer waters and higher food loads mean:
- Harmful algal blooms
- Oysters and fish deaths
- Danger to human health
©NRDC

14. Implicationsof climaticchangesonwatersystems (Oceans)
❑ The ocean absorbed 93% of the heat and sequestered 30% of the carbon dioxide during
the period from 1901 to 2010, which will affect the regularity of the Earth's climate.
❑ Ocean circulation redistributes heat and fresh water around the world which affecting
local climates.
❑ It is also expected that global ocean surface temperature increase will increase thermal
stratification, which may limit the depth at which water escapes, and thus the amount of
nutrients brought to the near surface.
❑ The ocean's absorption of increasing amounts of carbon dioxide from human activities is
acidifying the water, which can have adverse effects on aquatic life.
❑ Water acidity has increased by 26% since the industrial revolution and this will continue
It is expected that primary production in the oceans will decline by 3% to 9% by the year
2100.
Ocean acidification

15. Ocean
acidification
2
<1 1 >3
3
1850-1860
Corals
need this
Decade of:
1850 - 1860
2090-2100
What to expect
….lower carbonate
saturation state
Decade of:
2090 - 2100

16. What does increased ocean acidity mean?
1 cm
©Hazel
Oxenford
©Hazel
Oxenford
©Hazel
Oxenford
©Hazel
Oxenford
* Fewer carbonate ions, more hydrogen ions:
* Increased difficulty of building shells
*The frame of the reef may be eroded
* Nerve damage to fish larvae
* Low density fish replacement

17. High coral death rate
Loss of integrity of coral reefs
• Less living space for reef fish
and lobsters
. loss of coastal protection
coral death
©Hazel
Oxenford
Coral bleaching....
©Hazel
Oxenford
Includes
Coral bleaching

18. Impactsof climatechangeonfisheriesandaquaculture
* Changing the temperature will affect the various vital processes in it, such as mating
behavior, reproduction, egg laying and growth, increased susceptibility to diseases,
increased exposure to toxins and heavy elements, increased food consumption, increased
organic waste
* The lack of dissolved oxygen will lead to the migration of fish, the transmission of some
diseases and pathogens, the occurrence of genetic changes and the occurrence of
competition for food and the space available between the different species that are naturally
present in the place and the species arriving on them.

19. Impactsof climatechangeonfisheries andaquaculture
❑ It is expected that the production of fish will decrease, which will affect the
available quantity of fish meal and oils, which are mainly included as one of the
main components of fish feed.
❑ Increasing the susceptibility of fish to diseases and the speed of their spread,
especially bacterial and viral ones.
❑ The rise in temperature increases the metabolic rate, and thus increases the
intake of toxins and heavy metals surrounding the aquatic organism.

20. Fish Spoilage
Warmer temperatures:
Increases the possibility of
spoilage of fish
Increased incidence of
ciguatera poisoning
Marketing and Human Health
Effects
©Annabel
Cox
©Th.
Petit
le
Brun

21. ClimateChangesonEgypt
Egypt is considered one of the top five
countries that are expected to be vulnerable to
the effects of sea level rise, as most of the fish
farms in Egypt are located in the Nile Delta
region and are mainly concentrated in the
northern lakes (Mariout, Idku, Burullus and
Manzala). As a result of global sea level rise,
large areas of the Nile Delta coastal region are
expected to be subject to flooding.

23. Implicationsof climatechangeonaquacultureactivities
(water)
* The need for research to develop strains that tolerate lower water quality and higher
levels of brackish water could play an important role in the sustainable development of
desert aquaculture.
* Finding cost-effective technological solutions related to the extraction and
exploitation of brackish groundwater
* One of the most promising aquaculture technology is the Recycling Aquaculture
System (RAS), which requires about 20% of what is required by conventional open
pond culture.
* Bio floc technology is a technology to improve water quality by adding more carbon
to an aquaculture system.

25. Implicationsof climatechangeonaquacultureactivities
(Earth)
*Potential impacts on the delta may include increased coastal erosion, bypassing coastal
defenses and increasing flooding, damage to urban centers, receding sand dunes, reduced soil
moisture, increased salinity of soil and water in the lake, and decreased productivity of
agriculture and fisheries.
*Sea level rise leads to loss of land due to flooding, reduced area available for aquaculture,
loss of freshwater fisheries and aquaculture due to reduced availability of fresh water, and
changes in estuarine systems.
*Integration Aquaculture offers opportunities to adapt to climate change by integrating
aquaculture and agriculture (farming fish in a controlled environment) and hydroponics
(growing plants without soil, providing nutrients to plants mixed with plant-fed water) called
Aquaponics is a way forward for land use and water efficiently available, a sustainable food
production system that combines traditional aquaculture and hydroponics in a symbiotic
environment

26. Implicationsof climatechangeonaquacultureactivities
(Earth-integrateaquaculture)
Integrated aquaculture systems are the most cost-effective for several reasons:
❑It allows the farm to store water because it can take time to request water
from the irrigation area..
❑Help in irrigation with pressurized systems such as drip or sprinkler
systems..
❑Provides fish waste to fertilize crops..
❑Farmers have used the effluents for many crops, from vegetables and fruits
to wheat..
❑Productivity can be increased by using the same amount of water for two, or
three crops (fish, plant and animal products).

27. Implications of climate change on aquaculture activities
(Feed)
❑ The development of commercial aqua-feeds or complete feed diets is usually based
on the use of fishmeal as the main source of dietary protein..
❑ The nutritional properties of fishmeal protein are quite close to the nutritional
requirements of farmed fish.
❑ Plant proteins may be an alternative because they are widely available, and
affordable.
❑ There is an ongoing interest in identifying and developing ingredients as cost-
effective alternatives to good feed for fish meal.
❑ There are potential strategies to reduce feed production during the year. One option
is to store finished feed in temperature-controlled stores for sale in the high season.

28. Implications of climate change on aquaculture activities (Fry)
* Climate change is expected to have impacts on ocean productivity and fish
migration and employment, so more efforts must be made to increase hatchery
production..
* Other adaptation advantages can include research and genetic selection of fry that is
best adapted to new environmental condition.
* The expansion of the aquaculture industry in Egypt has coincided with the
development of a large number of tilapia hatcheries, all of which produce
monosexual fry and fingerlings. .
* A major challenge is that temperatures in summer are very suitable for the growth
and reproduction of the species (25-30°C). and in winter they drop below optimum
levels for growth and reproduction (16-6°C).
* Hatchery larvae can also contribute to the conservation and improvement of
endangered species, and can provide restocking to enhance fisheries.

30. Possible and proposed solutions for adapting aquaculture to climate change
❑ Marine aquaculture, aquaculture and integrated agriculture must be developed through the
use of groundwater and effluent discharge in order to overcome the current and projected
future constraints of freshwater and brackish water..
❑ Water and land resources will be a limiting factor for aquaculture development, and the
intensification of the current production system must meet the limitation of resources.
❑ An increase in the efficient use of land, water, food, seed and energy through
intensification (recycling and bio floc systems), which uses less land and fresh water, but
has higher energy and feed requirements, could result in the use of alternative renewable
energy systems and feed (non-marine) sources To greatly improve the sustainability of
reuse.
❑ Finding alternatives to fishmeal in the diet as a source of protein, and reducing the amount
of fishmeal and imported feed ingredients through the use of local species.
.

31. ❑ Increased fry production in hatcheries, genetic selection of fry that are better adapted to new
environmental conditions, and conservation and improvement of endangered species.
❑ The trend to expand marine hatcheries.
❑ Reducing energy use and proper energy management in feed manufacturing, using possible
renewable energy approaches in the aquaculture industry.
❑ Awareness and capacity building by providing education on climate change and creating
greater awareness among all stakeholders.
❑ Aquaculture may provide opportunities to reduce and mitigate greenhouse gas production
and carbon sequestration through good aquaculture production practices.
❑ There are opportunities to reduce greenhouse gas emissions in aquaculture, by improved
technologies for increased efficiency, use of renewable energy sources, and improved feed
conversion rates.

32. ❑ Improving farm management and selection of cultured species.
❑ Improving the selection of the appropriate site for farms, taking in the mind the risks
related to the climate.
❑ Improving environmental monitoring that includes users.
❑ Improving local, national and international coordination of prevention and mitigation
actions.
❑ The tendency to acclimatize saltwater fish to low or medium salinity.
❑ Research to develop new strains of aquaculture species that tolerate lower water quality
and higher levels of salinity.
❑ Reducing the discharge of various pollutants into lakes.
❑ Making mathematical models of the relationship between air and water temperature in
farm ponds and water depth.
❑ Fuel use and greenhouse gas emissions should be important considerations when
developing fisheries management strategies and other relevant management controls.

33. ❑ Conducting research related to knowing the rate of increase in the salinity of the
ground water of the delta and the salinity of waste water.
❑ Reducing the gases resulting from industrial activities and not burning agricultural
residues, and disposing of them in a healthy and safe manner.
❑ Controlling pathogens and their spread through strict health control of imported
biological species, and following the bio-safety system for fish farms and hatcheries.
❑ Increasing the use of water and improving breeding methods, monitoring the water
quality of the resulting products and its impact on human health, and integrating
aquaculture and agriculture as aquaponics system, to conserve water and increase the
productivity of fish and vegetable crops.

34. It is worth noting that not all future climate
changes will be negative, but rather positive
Example: Egypt is one of the countries located in
the semi-tropical areas and its delta is prone to
drowning, but the rise in the water level and the
increase in sea water will increase the production
of marine fish of high economic value as well as
raising the water temperature that makes us able to
cultivate good species with a change in the social
activity of the inhabitants of the delta so that they
tend to cultivate many types, which brings them
good profits and leads to raising the standard of
living.