INTEGRATION OF MANGROVES AND AQUACULTURE J.H. Primavera SEAFDEC - - PowerPoint PPT Presentation

INTEGRATION OF MANGROVES AND AQUACULTURE

J.H. Primavera SEAFDEC Aquaculture Department Tigbauan, Iloilo, Philippines

• Aquaculture
• Mangroves
• Are they compatible?
• Mangrove-Friendly Aquaculture in Asia
• Mangroves as aquaculture filters
• Mud crab culture in mangrove pens
• Mangrove rehabilitation (typhoons, sealevel rise)

• Gracilaria

fixed bottom

• !" #!$ %!
• &$%!
• polyculture,

carps, catfish pens intensive

• !"#!$

#

''()'&*

!

• +,,-. !

(85.9 million mt, US$66.7 billion)

/012+,0/3 450253

• 0/2+,063

780-217073 +808281063 +10928,0+3 Source: FAO Yearbook 2006

Philippine fisheries production

World Aquaculture Production 1950s: 1 Mmt 2006: 67 Mmt (42% total fisheries prod.)

5( " # $ % & ' ( ') * + , - . / 0

(5 (' 868:;9,,<,,, 867,;-8<,,, 8667;8+,<,,, 8667;+1+<,,,

MANGROVE: POND RATIO ,09;8

(5 (' 868:;9,,<,,, 867,;-8<,,, 8667;8+,<,,, 8667;+1+<,,,

MANGROVE: POND RATIO ,09;8

PHILIPPINES

'1 '

• 2-

&3 4+

• "."33
• 5
• ,3"33
• %

&*3333 (*($"33 &$6(*

• (333

,($(33 $*6&$

• &./,33
• ,3333

",3.33 (36/3 7 $33333 $,("33 *36.3 8 $33333 $*$(33

• 7

/"(333 ,&".*33

• 2

,* &*

• SE ASIAN MANGROVES & SHRIMP CULTURE

(=25! 0<+,,83 *(2

• $9"2

&*2 ":/3 *$2

• (5>*

(*

• );

8-?8:@A 80+9%!!

*(B'= 1975 1989

North Bais Bay, Negros Or., Philippines (Walters, 1996)

1950 1950

1996 1996

Rio Chone Delta, Ecuador (Redmanglar SNF)

Carbine (1932): “Mangrove … swamps are ideal for fishpond sites. Most of [these] are removed … only a few should be left for shade” Carbine (1948): “… the bangos [milkfish] industry is important because it made use of … practically valueless [mangrove] land.” Ling (1977): “Aquaculture has … served to reclaim largely unproductive land.Thousands of hectares of mangrove swamps … have been converted into productive fishponds …”

BIOGEOGRAPHICAL DISTRIBUTION OF MANGROVES (Duke, 1994) AND PRAWNS (Chong et al., 1996)

MANGROVE-FISHERIES CONNECTION

%&

• '&
• ()&

!!"" !$*& " +,*&#$%&

• ./,012&"

#

'3$$)04

/&* 5 1' 66!

# C0@A

8+?+7 8+?+7

!

8?9 8?9

A!

8+ 8+

• 2

Nutrients in effluents drained into natural mangrove stand

;× 9 <#&< 8 7$= ;" 393/3× .3(33> *,&$9333 ">, ;$ 39$&. × &*$33> /&&39,,.

• ,089:
• <6:80111@*1?

<?&< 8 ;" 39.&&× .3(33> *",$,9,,. ;$ 39$&& × &*$33> /$"&9&&&

• ,07:1

+6<6+,0111@(1? 7< ,:/"9&&&<#&< @$::$39333 <?&< 1-<6,80111@0 &,:3"9&&&9< ÷ &$3 $ %- 889018/@0+ @

A%23%%!!@A

' () # *+%,-,"./

+#(, , #(+ (6#(6 #,,

1!1()2 3,*,

• #(6#,,
• ,7

!,!! "4 " /(

• "/

!,!/kg feed/kg shrimp/d (8+kg shrimp/ha mng &*501,375 kg @ 20 g = 68,750 pcs/ha

(harvest) @ 30 g = 45,833 pcs/ha

• ,6,4

2!2,/ 4,27 '!/,'1 1, /

A%!%%"@A

Rate × water vol. 0.158 NH3-N mg/L/d = 6,981 mg NH3-N/d (1 d = 6 h) 0.483 NO3-N mg/L/d = 29,920 mg NO3- N/d Impounded Mangrove (area) 36,902 mg tot. N/d ÷ 320 m2 = 115.3 mg tot. N/m2 mng/d

++7,/

$9:,9* "9($9$ % '9 7 ,9( ,9( '9 A 9 "::. $9/ $9( '9 $"9. .9$" % ;B 0"::* .9/$ /9:, % 4 B "::*

• @A;

!23

• %

@A;!!% !A!%%

97 668

Summary & Conclusions

• passing pond effluents through mangroves reduced nutrient

levels (in day but not night)

• reduced nutrients due to biol. transformation (plant uptake,

denitrif.), rather than physical dilution (nighttime increases) or tidal flushing

• nutrient removal function of mangroves supports paradigm

shift for aquaculture to clean up effluents before release

• mangrove: pond ratio for effluent processing: 2-9:1 for N,

2-22:1 for P

• implications for Philippines: compliance with national laws:

greenbelt (20-, 50- and 100-m) and mangrove rehabilitation

• f abandoned ponds
• need to reverse present 0.5 ha mangrove: 1 ha pond ratio in

the Philippines

"!@A "!@A

2.6 3.6 Payback period (years) 38.5 % 27.5% Return on investment 83.90 Negative Net return yr-1 (2 crops) 41.95 Negative Net returns crop-1 7,033.89 5,018.88 Net cash return yr-1 (2 crops) 3,516.95 2,509.44 Net cash return crop-1 24,425.23 23,171.01 Total operating cost run-1 3,475.00 3,475.00 Sub-total 1,500.00 1,5,00.00 Caretaker’s salary 1,975.00 1,975.00

Non-cash costs:

Depreciation 24,467.18 22,205.45 Revenue Total Value (PhP)a Total Value (PhP)a Item 82 kg 164 kg 74 kg 148 kg Production: 1 crop 2 crops 252 g 211 g Corresponding body weight (Table 5) 37.2% 40.4%[ Survival rate (Table 5) Pellets + Fish Biomass Fish Biomass Production data

Cost and return analysis for 1000 m2 mud crab Scylla serrata pens using two feeding treatments.

0.59 0.45 0.52

Shannon Index

• f Sp. Diversity

13.5 13.9 8.05 7.07

Total

7.8 8.2 6.45 5.96

Trees

3.9 39.6 1.41 1.01

Saplings

1.8 90.0 0.19 0.10

Seedlings Basal area (m2 per ha)

104,633 70.3 15,950 9,368

Total

1,267 37.1 1,600 1,167

Trees

12,533 39.9 5,003 3,216

Saplings

90,833 97.6 9,850 4,984

Seedlings Stems/ha Jan 2004 % change Jan 2004 May 2002 Control Pens

Impacts of crab pen culture on mangrove community structure in Zarraga, Aklan, central Philippines.

Conclusions

• Incomplete, low-cost pellets can replace fish requirement in

mud crab diets

• Economic analysis showed viability of crab culture in

mangrove pens using fish biomass + pellets to reduce requirement for (low-value) fish, a food item of poor coastal communities

• Presence of crabs results in fewer mangrove seedlings and

saplings, but did not affect trees

Code of Practice for Sustainable Use of Mangrove Ecosystems for Aquaculture in Southeast Asia

• !""#

@ !

• C

C ! C !

IFS – small-scale, labor intensive

Mangrove conservation in Iloilo and Aklan provinces thru --

• education
• local governance

Mangrove Instructional Materials Production for Elementary Level

Module Writers - Purita P. Bilbao, Crisanto Lopez, Jr., Ruth L. Gelvezon, Marievic M. Violeta

Module 1. Starting a Walk to the Mangroves Module 2. Mangroves: Forests Growing by the Sea Module 3. Mangroves: Take a Closer Look Module 4. Mangroves: Our Natural Treasure Traditional uses (Forestry/ Fishery Products) Services Ecological Benefits Social Benefits Values Derived Medicine Wildlife Habitat