Comparing Bird Deterrent Strategies to Increase Sustainability and Production of Fruit Crops in Hawaii

Final report for FW19-350

Project Type: Farmer/Rancher
Funds awarded in 2019: $18,620.00
Projected End Date: 12/01/2021
Host Institution Award ID: G257-19-W7501
Grant Recipient: Mauka Vista Farms LLC
Region: Western
State: Hawaii
Principal Investigator:
Paul De Filippi
Mauka Vista Farms LLC
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Project Information


Comparing Bird Deterrent Strategies to Increase Sustainability and Production of Fruit Crops in Hawaii.

Birds are responsible for damaging many high value fruit crops in Hawaii, making a significant detrimental economic impact for local farmers and creates barriers to entry for new farmers. They spread disease and ruin crops.  These affected crops include dragonfruit, figs, mangos, lychee and longan.  Farmers are presented with various methods of protection and deterrence.  Many of these methods are expensive, labor intensive, impractical and often ineffective.  The subject research looks to examine the cost/effectiveness of two conventional methods of bird pest deterrence, and compare it to one novel method.  The methods are conventional netting (exclusion), conventional reflectors (visual stimuli), and an innovative method of utilizing an automated visible Agrilaser. 

Current practices include sound machines, hunting, bitterants, reflectors, bird netting, and bagging fruit before harvest.  These methods are problematic as the birds quickly adapt to these deterrents.  Netting and bagging are labor intensive, additionally the materials used are expensive and often do not survive an entire season.  Many fruit crops do not lend themselves to these practices due to the size of the tree or the fruit.

The project will test this innovative and humane form of pest deterrent in Hawaii and compare it against conventional methods for use on dragonfruit and fig crops.  The project will use a visible laser system to keep birds out of a specified area of crops.  This method differs from others in that the birds view the laser beam as a physical object, and they avoid it without adapting.  This system is mounted on a programmable base, so that the deterrent can be applied to any crop-producing field within a 6,500-foot radius.  The system is programmed once with the specific parameters of the area to be treated.  It can operate 24 hours a day, 7 days a week, within these parameters.

Project Objectives:
  • Design an executable set of trials.
  • Install Agrilaser equipment, conventional netting, and conventional deterrents.
  • Gather yield data for treated vs non-treated areas
  • Gather yield data for netted vs non-netted areas
  • Qualify cost/effectiveness.
  • Conclude which method is the most cost effective.
  • Present results through presentation, field-days, and on-line video to wide Hawaiian based audience on multiple islands.
  • Assist interested farmers in coordinating, attaining, and setting up the most cost effective methods for their operations.

See attached Gantt chart 


  • Site Work
    • Order Agrilaser and mount
    • Prepare netting control areas
    • Install mount and Agrilaser
    • Conduct trials and fruit count (2 times per month)
  • Reporting
    • Initial survey distribution and results
    • Monthly update report to HTFG and HFUU (verbal, photos)
    • Create online interactive videos/photos
    • Annual update report to HTFG and HFUU at conventions (written, photos)
    • Final survey distribution and results to CTAHR, HTFG and HFUU.
    • Finalize data and final report distribution to CTAHR, HTFG and HFUU.
  • Regional Education Activities
    • Hawaii Tropical Fruit Growers Conference 09/27/2020
    • Hawaii Farmers Union United Conference 10/27/2020
    • Hawaii Tropical Fruit Growers Conference 09/27/2021
    • Hawaii Farmers Union United Conference 10/27/2021
    • University of Hawaii, College of Tropical Agriculture and Human Resources Release 12/20/2021


Click linked name(s) to expand/collapse or show everyone's info
  • Paul De Filippi - Producer (Educator and Researcher)
  • Paul De Filippi - Producer (Educator and Researcher)
  • Paul De Filippi - Producer (Educator and Researcher)
  • Ken Love (Educator and Researcher)
  • Ken Love (Educator and Researcher)
  • Robin Shimabuku - Technical Advisor
  • James Simpliciano (Educator)


Materials and methods:
  • Materials
    • Agrilaser unit is a new treatment technique to Hawaii
    • Programmable base
    • Solar panel unit to provide AC power
    • Install one elevated pole with platform and ladder overseeing areas for laser coverage
    • Netting is a known treatment. Costly and labor intensive.
  • Methods and Design Summary
    • Agrilaser to sweep ~50% of area, leaving 17% as netted and 33% as unprotected using conventional visual deterrents.
    • Use of bagging and netting has been expanded
    • An addition treatment of Audio deterrent has been added
    • Emerging and matured fig and dragon fruit will be examined as they ripen.
    • Data for damaged and harvestable yield will be visually recorded
    • Laser will be in operation 24/7
    • Two growing seasons of data collection is recommended

Methods Detail (see attached Excel sheet, Tab 1, Data Recording)

Updated with COVID considerations and delays: SARE-Grant-Data-and-Timeline-Final

To measure the effectiveness (and success) of utilizing the bird laser deterrent method, we will visually compare and record the number of matured and emerging fruit production destruction levels from four controlled tree populations within the project space of 3 acres.

The plant categories are as follows:

1. Laser influenced trees - 39 fig/ 39 dragonfruit approximately 3 yrs old

Bird Laser system over fig and dragonfruit fields.

2. Netted trees using typical applications - 13 fig/ 13 dragonfruit approximately 3 yrs old

Reworked bird netting and non netted trees.

3. Un-netted trees  (ie. no laser coverage) - 26 fig/ 26 dragonfruit approximately 3 yrs old

Recording physical counts of fig predation will provide sufficient frequency data to measure the effectiveness of the laser.


  • Similar control design and effectiveness data recording will be implemented for the adjoining Dragon fruit area.
  • Resulting data will be tabulated and presented in graphical format
  • Still photography and video will be utilized to capture all aspects of the operation (materials and fruit destruction)
  • Known bird species to be affected by the operation will be summarized
  • Offsetting farm operations will be noted to detect propensity for bird migrations
Research results and discussion:

Trials were designed and set up by the project lead and the technical advisor.  There are four treatment areas: netted, lasered, traditional bird scares (no net, no laser), and a control.

Initial observations showed a greater effect on the larger species of birds predating on the fruit crops. Smaller species were also affect but when in large groups showed some resistance. There is more work to be done experimenting with intervals, frequency and patterns. 

Bird noise machines showed similar effectiveness, but required cycling and altering noise patterns. This effectiveness varied and did not affect all economically significant bird pest species

Bird scare devices and visual deterrents showed initial effectiveness, but required moving their locations and changing frequently over the test area. The deterrents were subject to damage in Hawaii weather patterns.

Bird netting has been shown to be labor intensive, and subject to destruction in Hawaii weather patterns. Netting has proven to be the best treatment, but requires a more robust installation.

While a combination of all treatments gave positive results, the cost, labor, and other negative effects proved to be significant. The losses in fruit we still significant in every treatment except for the netting and bagging. 

The netted group experienced some issues due to wind and required more maintenance and reinforcement. It has been updated and should provide a more complete data set this production period. Initial testing provided some limited data. Initial observations confirmed the greater amount of labor maintenance and material needed for this method. A more robust netting structure is suggested to withstand environmental factors.

One of the most important learnings from the trials is that different bird species react differently to each treatment. With Hawaii's wide diversity of invasive bird pest species, controls are quite marginal. The result of this study is to suggest that crop, location, weather patterns, bird species, profit model, and labor availability all be taken into account when choosing an appropriate control for bird pests. 

Mauka Vista Farms has chosen to continue the passive controls and add randomizations for many crops, while also incorporating low cost hoop house infrastructure for the crops that can be controlled for size. For the location, more substantial, permanent structures are needed to account for weather patterns and wind.

Results have been tabulated for 5 months of production in 2020. Results were recorded as a number of harvested fruit as compared to damaged or missing fruit.

Results have been tabulated for 5 months of production in 2021. Results were recorded as a number of harvested fruit as compared to damaged or missing fruit.

  Treatment Group     Treatment Group
2020 None Laser Netting/Bagging Audio Traditional Combination 2021 None Laser Netting/Bagging Audio Traditional Combination
N 52      78      52      52      18      32        N 52      78      52      52      18      32     
May Week 1 0.04 0.13 1.00 0.3 0.67 0.71   May Week 1 0.85 0.32 1.00 0.43 0.66 0.88
May Week 2 0.15 0.16 0.95 0.27 0.63 0.53   May Week 2 0.08 0.35 1.00 0.36 0.45 0.45
May Week 3 0.13 0.29 0.80 0.08 0.75 0.42   May Week 3 0.07 0.12 0.95 0.18 0.25 0.70
May Week 4 0.05 0.47 0.88 0.32 0.25 0.49   May Week 4 0.32 0.10 0.98 0.03 0.22 0.62
June Week 1  0.10 0.43 1.00 0.33 0.70 0.56   June Week 1  0.09 0.48 1.00 0.30 0.30 0.55
June Week 2 0.12 0.48 0.89 0.41 0.44 0.70   June Week 2 0.10 0.35 0.85 0.34 0.34 0.66
June Week 3 0.03 0.31 0.80 0.51 0.54 0.79   June Week 3 0.00 0.30 0.89 0.20 0.25 0.59
June Week 4 0.04 0.20 0.85 0.26 0.69 0.46   June Week 4 0.05 0.12 0.92 0.25 0.52 0.90
July Week 1  0.11 0.50 0.20 0.38 0.58 0.72   July Week 1  0.11 0.40 0.89 0.00 0.65 0.65
July Week 2 0.12 0.02 0.20 0.39 0.40 0.42   July Week 2 0.10 0.42 0.67 0.15 0.46 0.60
July Week 3 0.08 0.76 1.00 0.06 0.68 0.68   July Week 3 0.06 0.12 1.00 0.10 0.53 0.30
July Week 4 0.24 0.45 0.86 0.47 0.40 0.45   July Week 4 0.05 0.35 0.88 0.25 0.35 0.45
August Week 1  0.03 0.39 1.00 0.40 0.41 0.83   August Week 1  0.00 0.28 0.73 0.24 0.33 0.42
August Week 2 0.15 0.10 1.00 0.35 0.74 0.79   August Week 2 0.05 0.20 1.00 0.32 0.54 0.55
August Week 3 0.06 0.38 0.17 0.45 0.52 0.58   August Week 3 0.06 0.05 0.83 0.19 0.43 0.35
August Week 4 0.15 0.19 0.92 0.62 0.42 0.57   August Week 4 0.06 0.10 0.89 0.38 0.36 0.38
September Week 1  0.05 0.80 0.93 0.46 0.44 0.67   September Week 1  0.08 0.14 0.95 0.34 0.25 0.45
September Week 2 0.13 0.25 0.97 0.36 0.41 0.90   September Week 2 0.00 0.10 1.00 0.42 0.10 0.43
September Week 3 0.10 0.22 0.97 0.43 0.43 0.70   September Week 3 0.40 0.00 0.95 0.28 0.15 0.60
September Week 4 0.17 0.18 0.20 0.30 0.52 0.75   September Week 4 0.12 0.10 0.85 0.00 0.24 0.66
October Week 1  0.04 0.03 0.13 0.26 0.55 0.76   October Week 1  0.07 0.04 0.88 0.42 0.34 0.52
October Week 2 0.07 0.21 0.44 0.40 0.71 0.74   October Week 2 0.07 0.10 0.83 0.32 0.40 0.33
October Week 3 0.40 0.29 1.00 0.25 0.75 0.76   October Week 3 0.09 0.09 0.94 0.19 0.54 0.35
October Week 4 0.12 0.53 0.87 0.29 0.91 0.38   October Week 4 0.10 0.08 0.92 0.25 0.38 0.25
  10.95% 32.25% 75.10% 34.79% 56.40% 63.97%     12.34% 19.62% 90.81% 24.74% 37.67% 52.67%
                    *Laser stopped working in August.    


Untreated (control) showed that an average of 88% of dragonfruit and fig crops were lost due to bird pressure. This treatment group cost nothing in labor or materials.

The bird laser treatment and audio treatment showed that approximately 2/3 of the fruit were lost to bird pressure. Much of the second year's laser treatment data was discounted after the laser stopped working. The bird laser treatment group was expensive to implement, and was not completely reliable with the farms environmental factors (wind) and diversity of bird pressure. The audio treatment was cheap to implement and was similarly effective. Newer systems could show more viability for large acreages with high value crops. It is suggested that farmers work with the company and their representatives to ensure proper implementation and maintenance of the machine. Overall the results indicate that the bird laser system has an effect, and with rotation that effect was be higher, however there are cheaper options that require more labor and that may be more effective.

The bird laser is no longer functional and is outside of its warranty. It showed initial effectiveness in deterring some bird species from crops. This effectiveness wore off, despite cycling and reseting laser patterns. The laser did not affect all economically significant bird pest species. This treatment could be effective in the right circumstance.

The traditional system utilized a standardized rotation of adjustments to prevent the pests from getting accustomed to the deterrents. This showed to be an effective strategy, as did utilizing a combination of treatments. These treatments resulted in approximately 1/2 of the fruit being lost to bird pressure. All of these treatments required timely randomizations and upkeep to maintain effectiveness. The second year of data showed a decrease in overall effectiveness, possibly because the the pests became tolerant of the treatments, and the environmental conditions may have also contributed to this with less food alternatives available during a drought period. It has been hypothesized by the grant participants that the diversity of pest bird species complicates the system. When one species is successfully deterred by a treatment another species is still present and less affected, minimizing the effects.

The labor for the bagging of fruit was by far the most significant, followed by the traditional and combination treatments. The laser and audio had the least involved labor after mounting the equipment. The bird netting experienced increased labor because of severe weather events and coming into contact with the plants, better and more expensive infrastructure could solve this issue. once compromised the netting was severely less effective. This project has found the netting to be the most effective measure despite issues.

Properly implemented, durable netting systems are the most effective and low maintenance systems for bird protection. These can only be justified if the value of the crop is significant and the production model allows for the high initial cost.

Multiple consultations and and onsite visits were executed with participants reporting an increase in knowledge and plans to adapt successful treatments. The planned conference event and other speaking engagements have been delayed as a result of COVID-19. The project owner plans to resume outreach when the conferences are back next year.


Bird Species predating on fruit crops have been recorded and identified.

Meijito, Japanese White Eye





Jungle Fowl, 




Participation Summary
9 Producers participating in research

Research Outcomes

8 New working collaborations

Education and Outreach

8 Consultations
10 On-farm demonstrations
10 Tours
2 Webinars / talks / presentations
8 Workshop field days

Participation Summary:

180 Farmers participated
10 Ag professionals participated
Education and outreach methods and analyses:

Communication of Results

Over the proposed 2 year period of study, from inception to conclusion, the project manager will promote awareness of the project activity through regular exchanges with the University of Hawaii, College of Tropical Agriculture and Human Resources (CTAHR Extension Office), the Hawaii Farmers Union United ("HFUU") and the Hawaiian Tropical Fruit Growers association ("HTFG").  These are the three main beneficiaries of the results and provide the widest awareness to the general farming communities throughout Hawaii.

From the final data collection, results will be condensed both graphically and in text format into a shareable PowerPoint (PDF) presentation that will be emailed to the wider association of farmers through the current HFUU and HTFG membership and website information. These presentations will be also be disseminated through the University of Hawaii College of Tropical Agriculture and Human Resources, as well as the Hawaii Department of Agriculture.

Given the HTFG and HFUU hold monthly meetings on every island and the project manager is heavily involved in the both, verbal progress reports will be made as to the projects development.

Over the proposed 2 1/2 year study period, there are annual general meetings of the HTFG and HFUU, on the Islands of Hawaii, Oahu and Maui.  A more formal update report will be distributed at each agricultural forum (with photos) which are typically attended by over 300 individuals and companies representing both small and large farming concerns across Hawaii.

The project has been articulated and described at the annual HTFG Conference 2019 which occurred in Kona, Hawaii. Questions were taken and interest was gauged for field activities and presentations to each island and chapter. Updates were given at monthly meetings as well as the quarterly meeting of the board.

Field activities have been conducted with chapter representatives and other farmers and collaborators on Maui. So far HTFG has been the main recipient of the educational work. This is planned to expand to HFUU as well as CTAHR as more data and analysis come to fruition.

In person outreach has been limited due to Covid-19. The HTFG Conference 2020 and 2021 were both canceled. Final report to be provided to the organization for dispersal to membership and interested parties.

Outreach will continue once Covid restriction cease and conferences resume.

31 Farmers intend/plan to change their practice(s)
20 Farmers changed or adopted a practice

Education and Outreach Outcomes

130 Producers reported gaining knowledge, attitude, skills and/or awareness as a result of the project
Key changes:
  • Knowledge of alternative bird control methods, and their potential effectiveness.

  • Skills to implement bird control methods.

  • Confidence to plant highly affected crops.

  • Awareness of the project and goals.

Information Products

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.