EXISTENCE OF INVASIVE SPECIES AND ITS EFFECT ON FISHCAGES IN SELECTED MUNICIPALITY OF EASTERN LAGUNA INTRODUCTION • Philippines have a long history in the field of aquaculture, which involves different kinds of farming practices of different varieties of fish species in a diverse ecosystem. It contributes significantly to the country’s food security, employment and foreign exchange earnings. However in some past few years aquaculture experience a decline on its production and it was subjected on different problem which had been faced. Some of the recent studies focused on the impacts of invasive species on the field of aquaculture especially on fish pen and fish cages. BACKGROUND OF THE STUDY • IAS is among the top drivers of environmental change globally, and is known to threaten food security, human health and economic development. (Vitousek et al 1997) In the Philippines, data on the impact of IAS and to a number of anecdotal reports indicate that native species may be adversely affected through competition, predation, habitat alteration, and parasitism. Theoretical Framework of the study • This study adopts the theory of Evolution by Natural Selection of Charles Darwin. Conceptual framework The figure shows the interrelatedness of the variables. The first box which is the independent variable includes the different invasive organisms. The second box at the right side of the framework which is the dependent variable shows the production of some fish cage in Siniloan and Pakil Laguna. Independent Variable Dependent Variable Invasive Species Janitor Fish Gloria Production of Fish cages Jaguar Guapote GiantSnake Head Knife Fish Walking Catfish Objectives of the study • The study aimed to determine the existence of invasive species and its effect on fish cages in selected municipality of Eastern Laguna. This study wants to find out the different invasive fishes present in Siniloan and Pakil Laguna; the production of fish cages in Siniloan and Pakil Laguna; the effects of invasive fishes in the production of fish cages; and lastly to find out the significant relationship between the effects of invasive species exist and the production of fish cages in Siniloan and Pakil Laguna. Methodology • The researcher used the descriptive method. The respondents of this study were composed of eighty six (86) selected persons engaged in fish caging on Siniloan and Pakil Laguna. The respondents from Siniloan were thirteen (13) and seventy six (73) were from Pakil. To gather data a survey qustionaire was used. Results and Discussion Profile of the Respondents in terms of place, area and number of fish cages, fishes grown and method utilized in fish caging PROFILE Frequency Percentage Rank PLACE Siniloan 13 15.12% 2 Pakil 73 84.88% 1 Total 86 100.00% AREA (sq.meter) 4x10 – 4x20 3 3.49% 5.5 5x10 – 5x20 3 3.49% 5.5 6x10 – 6x20 17 19.77% 2 7x10 – 7x20 8 9.30% 3.5 8x10 – 8x20 47 54.65% 1 9x10 and above 8 9.30% 3.5 Total 86 100.00% NUMBER OF CAGES 1 – 10 32 37.21% 1 11 – 20 17 19.77% 2 21 – 30 14 16.28% 3 31 – 40 10 11.63% 4 41 – 50 7 8.14% 5 51 – 60 3 3.49% 6 61 – 70 3 3.49% 6 Total 86 100.00% FISHES GROWN ON FISH CAGES Big Head and Tilapia 35 40.70% 2 Tilapia 51 59.30% 1 Total 86 100.00% METHOD UTILIZED Extensive 76 88.37% 1 Intensive 10 11.63% 2 Total 86 100.00% Year and Place Encountered and Number of Invasive Fishes Observed by Fish cage Owners/Caretakers Year Encounter f % R Place Encounter F % R Number of Invasive f % R Fish Janitor Fish 1980-1990 54 62.79 1 Cage 13 15.11 2 High 58 67.44 1 2000-2005 15 17.44 2 Lake 73 84.88 1 Moderate 12 13.95 3 2006-2010 11 12.79 3 Market 0 0 3 Low 16 18.61 2 2011-2015 6 6.97 4 Gloria 1980-1990 4 4.66 4 Cage 46 53.48 1 High 50 58.14 1 2000-2005 13 15.12 2 Lake 39 45.34 2 Moderate 22 25.58 2 2006-2010 61 70.93 1 Market 1 1.16 3 Low 14 16.27 3 2011-2015 8 9.30 3 Jaguar Guapote 1980-1990 1 1.16 4 Cage 16 18.60 2 High 3 3.49 2.5 2000-2005 2 2.33 3 Lake 19 22.09 1 Moderate 3 3.49 2.5 2006-2010 5 5.81 2 Market 0 0 3 Low 29 33.72 1 2011-2015 27 31.39 1 Giant Snakehead 1980-1990 10 11.63 1 Cage 1 1.16 2.5 High 3 3.49 2 2000-2005 3 3.49 4 Lake 25 29.06 1 Moderate 0 0 3 2006-2010 5 5.81 3 Market 1 1.16 2.5 Low 24 27.90 1 2011-2015 9 10.47 2 Knife fish 1980-1990 0 0 4 Cage 32 37.20 2 High 60 69.76 1 2000-2005 2 2.33 3 Lake 53 61.62 1 Moderate 16 18.60 2 2006-2010 30 34.88 2 Market 1 1.16 3 Low 10 11.62 3 2011-2015 54 62.79 1 Catfish 1980-1990 61 70.93 1 Cage 13 15.11 2 High 10 11.63 3 2000-2005 20 23.25 2 Lake 73 84.88 1 Moderate 31 36.04 2 2006-2010 3 3.49 3 Market 0 0% 3 Low 45 53.32 1 2011-2015 2 2.33 4 Janitor fish ( Pterygoplichtys pardilis ) Gloria ( Sarotherodon melanotheron ) Jaguar Guapote ( Parachromis managuensis ) Giant Snake Head ( Channa micropeltes ) Knife fish ( Chintala ornata ) Walking Catfish ( Clarias batrachus ) (IMAGES OF INVASIVE SPECIES BASED ON BUREAU OF FISHERIES AND AQUATIC RESOURCES-DEPARTMENT OF AGRICULTURE) Production of Fishes in Fish Cages, 2000 – 2015 90 80 70 60 50 high moderate 40 low 30 20 10 0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 Level of Effect of Invasive Species in Fish Cage, Native and Cultured Fishes, and Environment of Fish Cages Level of Effect of Invasive Species in Fish Cages EFFECT IN CAGES Mean Verbal Interpretation Rank 1. Invasive fishes destroy nets and 2.81 Slightly Serious 4 other structural components of fish cages. 2. Invasive species allows culture 2.51 Not a Problem 5 fishes to escape from fish cages. 3. Invasive fishes are caught inside 3.06 Slightly Serious 3 the fish cages. 4. Eggs of invasive fishes found 3.26 Slightly Serious 2 inside or outside the fish cages. 5. Invasive species competes for 3.75 Moderately Serious 1 food and space with culture fish on the cages. Total 3.08 Slightly Serious Level of Effect of Invasive Species in Native and Cultured Fishes EFFECT IN NATIVE AND Mean Verbal Interpretation Rank CULTURE FISHES 1. Invasive species lessen fish caught 3.81 Moderately Serious 3 on lake’s open water. 2. The possibility to catch invasive fishes 3.66 Moderately Serious 4 is much higher than the possibility to catch the native one. 3. Invasive species preys or eats small 4.22 Very Serious 1 fishes. 4. Invasive species are caught at the 3.22 Slightly Serious 5 same place and time with native fishes. 5. Smaller fishes which can serve as 4.04 Moderately Serious 2 food for the native and culture fish is eaten by invasive species. Total 3.79 Moderately Serious Level of Effect of Invasive Species in the Environment of Fish Cages Environment of Fish Cages Mean Verbal Interpretation Rank 1. Pollution on the lake. 4.60 Very Serious 1 2. Poor quality of water. 4.55 Very Serious 2 3. Presence of disease and some 2.60 Not a problem 4 pathogenic parasites. 4. Invasive species interrupt the 3.67 Moderately Serious 3 growing process of the culture fishes. 5. Feces and other wastes product of 2.42 Not a problem 5 invasive species. Total 3.57 Moderately Serious Relationships between the Effect of Invasive Species in Fish Cages and the Production Variable Stat. Tool Df Comp. P-Value Decision Interpretation Value Effect of Invasive Species in Fish Cages 2000 6 3.704 0.717 Accept Ho Not Significant 2001 6 3.76 0.709 Accept Ho Not Significant 2002 6 1.795 0.938 Accept Ho Not Significant 2003 6 0.928 0.988 Accept Ho Not Significant 2004 6 2.225 0.898 Accept Ho Not Significant 2005 6 8.502 0.204 Accept Ho Not Significant 2006 6 2.418 0.878 Accept Ho Not Significant 2007 Chi Square Test 3 0.214 0.975 Accept Ho Not Significant 2008 of Association 6 7.976 0.240 Accept Ho Not Significant 2009 6 12.394 0.054 Accept Ho Not Significant 2010 6 9.396 0.153 Accept Ho Not Significant 2011 6 22.332 0.001 Reject Ho Highly Significant 2012 6 11.609 0.071 Accept Ho Not Significant 2013 6 6.314 0.389 Accept Ho Not Significant 2014 6 5.921 0.432 Accept Ho Not Significant 2015 6 9.007 0.173 Accept Ho Not Significant Relationships between the Effect of Invasive Species in Native and Cultured Fishes and the Production in Fish Cages Variable Stat. Tool df Comp. P-Value Decision Interpretation Value Effect of Invasive Species in in Natural and Cultured Fishes 2000 4 16.01 0.003 Reject Ho Highly Significant 2001 4 8.13 0.087 Accept Ho Not Significant 2002 6 3.336 0.766 Accept Ho Not Significant 2003 4 6.119 0.190 Accept Ho Not Significant 2004 4 12.741 0.013 Reject Ho Significant 2005 6 8.502 0.204 Accept Ho Not Significant 2006 4 7.503 0.112 Accept Ho Not Significant 2007 Chi Square Test 2 3.12 0.210 Accept Ho Not Significant 2008 of Association 4 7.131 0.129 Accept Ho Not Significant 2009 6 12.394 0.054 Accept Ho Not Significant 2010 6 4.071 0.667 Accept Ho Not Significant 2011 6 22.332 0.001 Reject Ho Highly Significant 2012 6 7.121 0.310 Accept Ho Not Significant 2013 6 16.866 0.010 Reject Ho Significant 2014 8 20.759 0.008 Reject Ho Highly Significant 2015 8 10.766 0.215 Accept Ho Not Significant Relationships between the Effect of Invasive Species in Environment and the Production in Fish Cages Variable Stat.