The palmweevil Rhynchophorus vulneratus is ), removed was by aprofes The estimated cost oftheeradication was $1,003,646. Island date palminLaguna Beach. recovered from aninfested Canary Adult maleRhynchophorus vulneratus 8, 2016 September online Published http://dx.doi.org/10.3733/ca.2016a0012Online: Southern CaliforniaSouthern landscapes. Arapid, led to the deployment coordinated effort USDA-APHIS declared thisweevil eradicated from California onJan.20, 2015. Mediterranean, the Middle East and North Africa,Mediterranean, anditsdiscovery East theMiddle inCalifornia andNorth caused applications to privately advanced ofpalmsat owned palmsanddestruction stages Beach, California.Beach, ofpalmsinthe The red palmweevil hascaused mortality extensive Laguna The Beach. lastconfirmed ofalive detection R.vulneratus was Jan.20,2012. In October 2010,Rhynchophorus vulneratusIn October identifiedasthe , originally red palm of infestation. Researchof infestation. confirmed the chemical ofthe aggregationcomponents of traps baited withtheweevil’s aggregation pheromone, coordinated pesticide concern for thestate’s ornamentalpalmanddate industriesandthemany palmsin identity, native range andputative region detected in oforiginfor thepopulation weevil, R.ferrugineus, was discovered Islanddate palmsinLaguna infesting Canary sional arborist in Laguna Beach, Orange Orange Beach, Laguna in arborist sional by County, California. Examination of the of the Examination County, California. pheromone, assessedtheefficacy of trapping strategies and resolved thetaxonomic eradicated from LagunaBeach O Research Article Research Mark S.Hoddle, D. Mark Christina Hoddle, Alzubaidy, Mohammed Dimson andMonica Jocelyn Millar J. Nisson, Nicholas JohnKabashima, canariensis Chabaud canariensis Phoenix , Island Canary n Aug. 3, 2010, abadly damaged (: (Arecales: - covery of adult and larval weevils (Cole weevils covery of adult larval and re the in resulted arborist by the crown optera: ). This material was was material optera: Curculionidae). This tion on Sept. 1, Sept. on tion 2010, California the and office for commissioner’s identifica tural submitted to the Orange County agricul County Orange to the submitted http://calag.ucanr.edu - - - - These two find sites were 0.07 miles sites find were miles (0.12 two 0.07 These (CDFA)the adult identified subsequently (Olivier) (Coleoptera: Curculionidae), the the Curculionidae), (Coleoptera: (Olivier) city has no airport, seaport or interstate or interstate seaport no airport, has city Department of Food and Agriculture Agriculture of and Food Department Route 133, run through Laguna Beach; the the Beach; Laguna Route 133, through run Route 1, highway, west-east one and State (USDA) of Agriculture on Department the States United by confirmed was kilometers) apart. apart. kilometers) at the CDFAat the USDA and (Hoddle 2010a). oped San Joaquin Hills, to the east. One One east. to the Hills, Joaquin San oped palm in Laguna Beach. The weevil was was weevil The Beach. Laguna in palm habitants), relatively wealthy isolated, res the west, and the dry, west, the the and relatively undevel heavily damaged Canary Island date Island Canary damaged heavily idential area between the Pacific Ocean, to PacificOcean, the between area idential identified as identified red palm weevil. weevil. palm red - 23,250 kilometers], [23 in square miles male weevil was recovered from a second asecond from recovered was weevil male Rhynchophorus ferrugineus Rhynchophorus as specimens north-south highway, California State highway,north-south California

Sept. 24,Sept. 2010. 26, Oct. 2010, On a live adult •

The CDFA’sThe tentative identification Laguna Beach is a small (~ asmall is 8.8 square Beach Laguna PUBLISHED ONLINE R. ferrugineus R. SEPTEMBER 8, 2016 by specialists by specialists

- 1 -

John Kabashima (A) (B) Mark Hoddle Mark Hoddle

Fig. 1. Two color morphs of Rhynchophorus vulneratus recovered from an infested palm in Java, Indonesia. (A) The orange and black morph of R. vulneratus (left) is very similar in appearance to R. ferrugineus. The black morph with the red dorsal stripe (right) is similar to adult R. vulneratus recovered in Laguna Beach. (B) Two color morphs of R. vulneratus copulating. border crossings. Tourism is a major in- Weevil biology in Laguna Beach were officially identified dustry, with ~ 3 million people visiting as R. ferrugineus. the city annually (Turnbull 2004). Palm mortality caused by R. ferrugin- Subsequent work investigating the Rhynchophorus spp. weevils, especially eus results from internal feeding by larvae origin of the palm weevil invasion in R. ferrugineus, are notoriously destructive (mature larvae can exceed ~ 2 inches [5 Laguna Beach used molecular markers palm pests in native and invaded ranges centimeters] in length), which are con- to investigate the identity of the (Faleiro 2006; Murphy and Briscoe 1999). cealed within the palm during the entire detected and to ascertain its probable area R. ferrugineus attacks more than 40 palm larval life cycle, making detection of early of origin. DNA-based analyses of weevils species in 23 genera. It is a destructive infestations and subsequent control dif- collected throughout the presumptive pest of the coconut palm, Cocos nucifera ficult (Giblin-Davis et al. 2013). Internal native ranges of R. ferrugineus and R. vul- L. (Arecales: Arecaceae), (Giblin-Davis et feeding by two or three generations of neratus concluded that the weevil species al. 2013) in its native range, which is the weevil larvae over 1 to 2 years can kill collected in Laguna Beach was R. vulnera- northern and western regions of continen- infested palms. Palm death results from tus, a species distinct from R. ferrugineus. tal Southeast Asia (e.g., northern Thailand, mortality of apical growing areas (typical Molecular analyses by Rugman-Jones Vietnam and Cambodia), Sri Lanka and for C. nucifera and P. canariensis) or trunk et al. (2013) indicated that R. vulneratus the Philippines (Rugman-Jones et al. 2013). collapse (typical for P. dactylifera) (Faliero has a native range confined largely to Accidental introduction of R. ferrugineus 2006; Giblin-Davis et al. 2013; Murphy and southern Thailand and northern Malaysia into regions outside of its native range Briscoe 1999). on the Malay Peninsula, Singapore, and has occurred via the movement of live A second Southeast Asian palm Indonesia, and that this species has a palms infested with weevils, and this weevil species, R. vulneratus (Panzer), range of color forms, including that typi- pest has caused extensive mortality of P. was reported to have a more southern cal of the invasive R. ferrugineus (fig. 1). canariensis in the Mediterranean and of distribution in Asia than R. ferrugineus The results of these molecular studies date palms (Phoenix dactylifera L.) in the (Wattanapongsiri 1966). A taxonomic on species identities and geographic Middle East and North Africa (Faleiro revision by Hallett et al. (2004), with distributions supported earlier work by 2006; Faleiro et al. 2012; Giblin-Davis et al. specimens collected from west Java, in Wattanapongsiri (1966). It was concluded 2013; Murphy and Briscoe 1999). Indonesia, separated the species primarily that Hallett et al. (2004) had been study- Discovery of red palm weevil in on the basis of color differences, with R. ing different color morphs of R. vulneratus California was of major concern because vulneratus typically being black with a red in Java and that R. vulneratus had been the ornamental palm and date industries stripe on the dorsal surface of the thorax incorrectly synonymized with R. ferru- are estimated, respectively, at $70 million and R. ferrugineus being orange with black gineus (Rugman-Jones et al. 2013). From and $34 million annually (CDFA 2013), markings). Unable to find any significant this point forward, we will refer to the and palms are ubiquitous in Southern molecular, morphological or behavioral weevil species found at Laguna Beach as California landscapes. Furthermore, the differences or mating incompatibilities R. vulneratus. native California fan palm, Washingtonia between these two color morphs, Hallett The only find of R. vulneratus outside filifera (Lindl.) H.Wendl. (Arecales: et al. (2004) synonymized R. vulneratus of its native range has been in Laguna Arecaceae), restricted to a limited range with R. ferrugineus, with R. ferrugineus Beach. The nearest molecular match to comprising desert riparian habitats in the having naming priority. Therefore, the the Laguna Beach population was with western , was considered black palm weevils with a prominent red R. vulneratus collected in Bali, Indonesia vulnerable because it is a known host for stripe on the dorsal surface of the thorax (Rugman-Jones et al. 2013). It was hypoth- R. ferrugineus (Ju et al. 2011; Longo et al. (i.e., the R. vulneratus morph) discovered esized that the introduction of R. vulnera- 2011). tus into Laguna Beach may have been

2 CALIFORNIA AGRICULTURE • DOI: 10.3733/ca.2016a0012 (A) (B) Mark Hoddle Mark Hoddle

Fig. 2. adult (A) and larva (B) extracted from a cocoon of palm fibers. Both were collected from an infested Phoenix canariensis in Tijuana, Mexico. This weevil was detected as a result of the public’s response to requests for help with the R. vulneratus invasion in Laguna Beach. R. palmarum may have established in San Diego County and potentially poses a serious threat to California’s palms.

deliberate, possibly to start a local source 6 square kilometers of the initial find sites in Laguna Beach. The TWG included in- of palm weevil larvae and pupae to be were conducted by CDFA over the period ternational palm weevil experts, research used in the preparation of traditional Sept. 27, 2010, to Oct. 28, 2010. Detection scientists from UC Riverside, CDFA Asian dishes (Hoddle 2015). of empty pupal cases or body fragments and USDA, UC Cooperative Extension of dead adult weevils confirmed the pres- personnel from San Diego, Orange and Response in Laguna Beach ence of this pest in five survey locations. Los Angeles counties and county ento- Visual surveys were aided by a large re- mologists from the agricultural commis- To delineate the areas in Laguna sponse from residents, local arborists and sioner’s offices in Orange and San Diego Beach infested by R. vulneratus, 1-gallon palm enthusiasts. Reports of symptomatic counties. (3.78-liter) bucket traps were loaded with palms by these groups were investigated The TWG met at Laguna Beach from Ferrolure 700 mg (ChemTica Internacional by CDFA and Orange County program Nov. 29 to Dec. 1, 2010 (Hoddle 2010b). S.A., Costa Rica), which contains the ag- personnel, and cooperating home own- The group produced a document with gregation pheromone 4-methyl-5-nonanol ers provided access to private properties. recommendations pertaining to (1) detec- (ferrugineol). Also in the bucket were Survey results in Laguna Beach indicated tion and identification of visual symp- ethyl acetate (a synergist), fermenting that the area infested with R. vulneratus toms typifying infestations, (2) trapping apples as bait and 0.26 gallon (1 liter) of a was ~ 0.39 square miles (1 square kilo- guidelines, (3) assessment of techniques 50:50 mixture of water and propylene gly- meter), which equated to ~ 4% of the land for early detection of infestations, (4) pes- col (to drown and preserve weevils). area of the city of Laguna Beach. ticide treatments, (5) removal and destruc- Trapping commenced Oct. 7, 2010. A The public response to outreach ef- tion of infested palms and (6) education, total of 150 traps were deployed by CDFA forts and subsequent surveys resulted outreach and information dissemination at two different densities within a survey in another pest discovery in Southern to local communities and palm industry area of 6 square miles (15.6 square kilo- California: the first confirmation of the professionals (Hoddle 2010c; Hoddle meters; ~ 68% of the land area of Laguna South American palm weevil, R. pal- 2011b; Hoddle 2011c). Beach). High-density trapping was set marum (L.) (fig. 2), in California and the Despite evidence of damaged palms at 50 traps per 1 square mile (2.6 square neighboring state of Baja California, in Laguna Beach, baited pheromone traps kilometers) around find sites. Outside of Mexico (Hoddle 2011a). The high mortal- captured only one adult weevil, which this zone, 25 traps were deployed per 1 ity of Canary date palms in Tijuana since was found on Jan. 18, 2012, within 0.21 square mile (2.6 square kilometers). Two at least 2011 has been the source of wee- kilometer of the original find sites. In re- additional traps (total number used for vils entering Southern California, and it sponse to this find, between Jan. 31, 2012, monitoring was 152) were deployed at a is likely that R. palmarum will become a and Feb. 15, 2012, visual surveys of palms green waste facility 15 miles (24 kilome- problematic pest of ornamental, date and for weevil infestations were conducted by ters) south of the find sites to monitor for native palms in California, as there are CDFA within an area of 0.6 square miles weevils inadvertently moved there in dis- increasing reports of P. canariensis being (1.6 square kilometers). A total of 5,564 posed palm material. Traps were attached killed by this pest in San Ysidro in San palm trees were inspected on 782 prop- to palm trunks ~ 6.6 feet (2 meters) above Diego County. At this time there are no erties. Two additional properties with the ground and inspected daily from active programs targeting R. palmarum in palms exhibiting characteristic weevil Oct. 7, 2010, to Oct. 17, 2010, weekly until Southern California. feeding damage to fronds ( notching March 19, 2011, then biweekly until Jan. 20, A technical working group (TWG) was or holes in the petiole base) were identi- 2015, when eradication was declared. assembled by the USDA to provide expert fied. However, weevil presence (pupal Visual surveys of 13,485 palm trees for input into the emerging monitoring and cases or adult weevils) was not confirmed. weevil damage on 1,963 properties within management program for R. vulneratus

http://calag.ucanr.edu • PUBLISHED ONLINE SEPTEMBER 8, 2016 3 (A) 6

1 The low capture rates of R. vulneratus in pheromone traps in areas with ap- parent or suspected weevil infestations caused concern because it suggested that the pheromone traps might not be attrac- tive to R. vulneratus. If this was the case, then the lack of a sensitive and species- 4 5 specific monitoring tool could sig- 3 nificantly impair the management program targeting R. vulneratus. 2 Verifying pheromone Christina Hoddle compounds Hallet et al. (1993) identified (B) two aggregation pheromone com- 2 Males ponents, 4-methyl-5-nonanone 30 (ferrugineone) and 4-methyl- 5-nonanol (ferrugineol), pro- duced by male R. vulneratus 20 (they incorrectly assumed that they were working with R. ferrugineus) collected in

10 1 Java, Indonesia. To verify the chemical identify of the aggregation pheromone of R. vulneratus as reported by Hallett et al. 0 (1993), male and female weevils were field collected by authors Mark and Christina Females Hoddle in Sumatra, Indonesia, and used for pheromone collection. 30 Pheromone collections and controls ) 5 consisted of four treatments: (1) a steril-

20 ized mesh container only, (2) four male weevils on a food source (either sugar- cane or oil palm hearts, used separately in 10 case one stimulated pheromone produc-

Abundance (10 tion), (3) four female weevils on a food source and (4) the food source used in 0 2 and 3 without weevils. All treatments were placed inside heat-sterilized mesh Oil palm control containers, which in turn were enclosed 30 by odorless Terinex oven bags (Terinex Ltd., Bedford, U.K.). The mesh containers held the weevils and food and prevented 20 weevils from chewing holes in the oven bags and escaping. Treatments 1 and 4 provided control 10 chemical profiles of volatiles from the mesh cage and the food sources, and treatments 2 and 3 provided profiles of 0 4 6 8 10 12 14 16 18 volatiles released by male and female weevils. An aquarium pump was used to Time (min) push purified air into the oven bags over Fig. 3. (A) Rhynchophorus vulneratus pheromone aeration set up in an outdoor screen house in Sumatra, Indonesia. (1) Terinex odorless oven bag enclosing a sterilized wire mesh container holding adult male the mesh containers, food and weevils, or female weevils with food (see inset photo). (2) Inlet with 6 to 14 mesh activated charcoal filter to and as the airstream exited, it was passed purify ingoing air. (3) Outlet with thermally desorbed 50 to 200 mesh activated charcoal collector to through activated charcoal filters, which collect volatile compounds emitted by weevils and food items. (4) Manifold to regulate airflow. (5) Aquarium pump to push and pull air through oven bags. (6) Airflow meters. (B) GC–MS chromatograms trapped the volatiles released into the air- of volatiles collected from male and female R. vulneratus and the oil palm (food source for weevils) space of the bags by the weevils or food control. Peaks 1 and 2 in the chromatogram for male weevils are 4-methyl-5-nonanone (ferrugineone) items (fig. 3A). and 4-methyl-5-nonanol (ferrugineol), respectively. Schematic prepared by Steve McElfresh.

4 CALIFORNIA AGRICULTURE • DOI: 10.3733/ca.2016a0012 Aerations were made continuously R. vulneratus (Hoddle and Hoddle 2015). pesticides Jun. 2, 2011 (Hoddle 2011e), for 3 to 4 days, and treatments were rep- The volatiles from cut palm logs likely then cut down and removed from a pri- licated four times. The trapped volatiles act synergistically with the aggregation vate residence in Laguna Beach on Mar. were eluted from the charcoal collectors pheromones to increase attraction (Hallett 27, 2013, because it was causing structural and analyzed by coupled gas chromatog- et al. 1993). damage to an adjacent building (Hoddle raphy–mass spectrometry (GC–MS). The A combination of traps and cut date 2013). The palm crown and petiole bases -produced compounds were tenta- palm trunks (date palms were used be- on individual fronds were examined for tively identified by interpretation of their cause coconut palms were not available) R. vulneratus feeding damage. There was mass spectra, and these identifications was tested in Laguna Beach to determine no visual evidence of feeding damage, were verified by comparing the GC reten- if it would result in captures of R. vulnera- and no larvae, pupal cases or adults (dead tion times and mass spectra with those tus in areas where activity was observed or alive) were found (Hoddle 2013). of authentic standards obtained from but no weevils had been caught in traps. ChemTica. Date palm sections were obtained from a The analyses showed that two male- commercial palm producer in Coachella specific compounds were produced by Valley, California. Three sites around ar- R. vulneratus in Sumatra, and they were eas with suspected R. vulneratus activity conclusively identified as the two previ- in Laguna Beach were selected for weevil ously reported aggregation pheromone monitoring with sections of date palm components obtained for R. vulneratus trunks and pheromone traps. from Java (Hallett et al. 1993) (fig. 3B). Sections of cut apical parts of palm This result raised an important question: trunks were stacked beside P. canariensis What are the aggregation pheromones for palms and baited pheromone traps were R. ferrugineus? The commercially available deployed on top of these stacks. Traps aggregation pheromone used for R. ferru- were checked daily from June 21, 2012, to gineus management was identified from R. July 17, 2012, for a total of 27 consecutive

vulneratus (Hallett et al. 1993), and to our days. No weevils were found in traps or John Kabashima knowledge, the identity of the aggrega- log stacks. This trial was repeated Oct. 18, Canary Island date palm killed by Rhynchophorus tion pheromone produced by R. ferrugin- 2012, to Nov. 11, 2012, a 27-day period. No vulneratus in Laguna Beach (note healthy Canary eus has not yet been determined, although weevils were recovered from the second Island date palms in the background). this species is attracted to baited traps trial (see Hoddle 2012 for more details). containing ferrugineol and ferrugineone Declaration of derived from R. vulneratus. Palm removals, and pesticides eradication, cost Field evaluations of On Nov. 3, 2010, the infested Canary On Jan. 20, 2015, USDA-APHIS of- Island date palm that yielded a live male ficially declared eradication of R. fer- baited traps weevil on Oct. 26, 2010, was removed rugineus (i.e., R. vulneratus) from Laguna The attractiveness of traps loaded from Laguna Beach and disposed of in Beach, 3 years after the last detection of with fermenting bait, ethyl acetate and compliance with strict destruction proto- a single live weevil on Jan. 18, 2012 (El- Ferrolure 700 mg was field-tested in cols (Hoddle 2010d). No live larvae, pupae Lissy 2015). The eradication declaration the Philippines (R. ferrugineus was the or adult weevils were found inside the was made in accordance with European species present at study sites on Luzon trunk or petioles. This palm was the only and Mediterranean Protection Island) and Indonesia (R. vulneratus was one removed as part of the R. vulneratus Organization International Standards, the species present on Sumatra). At the management program. which require a period of 3 consecutive time these field studies were conducted, it A total of 13 palm trees were treated years with no pest detections (El-Lissy was assumed that R. ferrugineus was the with broad-spectrum contact pesticides 2015). subject of this work and the only species applied to foliage and/or systemic pesti- Despite significant data supporting present in both countries. cides that were applied via trunk or soil R. vulneratus as the invasive weevil spe- In the Philippines, three different injections (Hoddle 2011d; Hoddle 2011e): cies in Laguna Beach (Rugman-Jones treatments were tested for attractiveness three P. canariensis (two with confirmed et al. 2013), USDA-APHIS states that it to weevils; traps were baited with (1) fer- infestations; treated once each), five will “continue to refer to this detection as menting dates or pieces of coconut palm forsteriana Becc. (suspected infes- Rhynchophorus ferrugineus until additional heart, ethyl acetate and aggregation pher- tations based on visual damage assess- information is available” (Molet et al. 2011, omone, (2) freshly cut coconut palm logs ments; treated three times from August to revised 2014). This stance is based on the only and (3) a combination of treatments December 2011), one Chamaerops sp. (sus- desire of USDA-APHIS for a combined 1 and 2 (Hoddle and Hoddle 2011). This pected; treated once) and four Roystonea dataset of morphological and DNA in- experiment was repeated in Sumatra and sp. (suspected; treated twice from March formation, as well as discrete species di- results were similar: baited pheromone to April 2012). agnoses, to resolve remaining taxonomic traps combined with freshly cut palm One P. canariensis with confirmed uncertainty (Eileen Smith, USDA-APHIS, logs, treatment 3, were very attractive to R. vulneratus activity was treated with personal communication, Mar. 31, 2015).

http://calag.ucanr.edu • PUBLISHED ONLINE SEPTEMBER 8, 2016 5 35 (A) The cost of the eradication of R. vulneratus from Laguna Beach was estimated at $1,003,646. A breakdown of estimated 30 expenditures is provided in table 1.

C) 25 Success factors

20 Eradication of an invasive pest depends on mul- tiple interacting factors. Specifically, small infested areas that can be monitored with highly specific and sensitive tools (e.g., 15 Denpasar, Bali pheromone-baited traps) have higher eradication success prob- Laguna Beach abilities. Furthermore, the smaller the area being treated, the 10 Average temperature ( ˚ less it costs to eradicate the target (Tobin et al. 2014). These fac- tors likely contributed, in part, to the successful eradication of R. 5 vulneratus from Laguna Beach. Social, economic, regulatory and political factors also are 0 critical components of eradication programs (Pluess et al. 2012). Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec These may include the authority of regulatory agencies to inter- Month vene and take action on private and public lands, procurement 400 of funds to support the project, the commitment and political (B) will of stakeholders affected by the invasion and, very impor- 350 tantly, strong public support for eradication efforts (Tobin et al. 2014). The R. vulneratus eradication effort benefited from strong 300 socioeconomic support. Organisms need to maintain populations above a critical 250 density, the Allee threshold, if they are to persist. Below this threshold, populations trend toward extinction (Liebhold and 200 Tobin 2008; Suckling et al. 2012). Factors negatively influencing Denpasar, Bali the Allee threshold and increasing extinction risk may include 150 Laguna Beach (1) unsuitable climate, (2) suboptimal foods, (3) low genetic Aerage rainfall (mm) 100 TABLE 1. Estimated costs for the program that eradicated Rhynchophorus vulneratus from Laguna Beach, 50 September 2010 to January 2015

0 Estimated Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec Expenditure item cost ($) Month Labor for visual inspections of palms and monitoring of baited 230,000 100 pheromone traps in Laguna Beach (C) Bucket traps and supplies for maintaining traps (pheromones, 32,000 , etc.) in Laguna Beach

80 Travel to monitor traps (vehicle rental and gas) in Laguna Beach 60,000 Salary estimates for CDFA, UC and county agricultural 230,000 commissioner employees involved in palm weevil monitoring, management and research 60 CDFA Specialty Crop Block Grant that supported molecular 108,446 analyses of weevils, testing of pheromones and trapping strategies in native and invaded ranges, and identification of 40 Denpasar, Bali aggregation pheromones collected from R. vulneratus in Sumatra, Laguna Beach Indonesia Pesticide applications to 13 palm trees in Laguna Beach 1,200

Aerage relatie humidity () 20 Four date palms used for enhanced trapping trials at Laguna 12,000 Beach ($3,000 per palm) Outreach and extension materials and community meetings for 30,000 stakeholders 0 Miscellaneous costs, including rental of bucket trucks (cherry 20,000 Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec pickers) to inspect palms; palm removal, transport and disposal; Month cameras, binoculars; etc. Statewide monitoring program for invasive palm weevils in other 280,000 Fig. 4. Average monthly comparisons between Laguna Beach, California, and areas of California, outside of Laguna Beach (998 traps deployed Denpasar, Bali, Indonesia for (A) temperature, (B) rainfall and (C) humidity. in 12 counties) Sources: www.usa.com/laguna-beach-ca-weather.htm and www.weatherbase.com/ weather/weather.php3?s=592525&cityname=Denpasar-Bali-Indonesia&units=metric. TOTAL 1,003,646

6 CALIFORNIA AGRICULTURE • DOI: 10.3733/ca.2016a0012 variability and (4) control tactics such as the use of pesticides. The interaction of References some or all of these factors may have con- CDFA [California Department of Food and Agriculture]. Hoddle MS. 2011e. Red palm weevil in Laguna Beach tributed to the successful eradication of R. 2013. California Agricultural Statistics 2013 Crop Year. dealt a second blow. http://cisr.ucr.edu/blog/news/ www.cdfa.ca.gov/Statistics/PDFs/CropYearStats2013_ red-palm-weevil-in-laguna-beach-dealt-a-second-blow/ vulneratus. NASS.pdf. (accessed Aug. 18, 2016). First, the climate in Laguna Beach may El-Lissy OA. 2015. Red palm weevil (Rhynchophorus fer- Hoddle MS. 2012. Testing a new trapping program for not have been suitable for vigorous year- rugineus) eradicated from California. http://content.gov- red palm weevil in Laguna Beach, California. http://cisr. delivery.com/accounts/USDAAPHIS/bulletins/eb0f5e ucr.edu/blog/uc-riverside/testing-a-new-trapping-pro- round population growth of the weevil. (accessed Aug. 18, 2016). gram-for-red-palm-weevil-in-laguna-beach-california/ Average monthly temperatures and rain- Faleiro JR. 2006. A review of the issues and manage- (accessed Aug. 18, 2016). fall are lower in Laguna Beach than in ment of the red palm weevil Rhynchophorus ferrugin- Hoddle MS. 2013. Has the red palm weevil gone extinct eus (Coleoptera: Rhynchophoridae) in coconut and date in Laguna Beach? http://cisr.ucr.edu/blog/mark-hoddle/ Bali, Indonesia (fig. 4), where weevils with palm during the last one hundred years. Int J Trop Insect palm-removal-in-laguna-beach/ (accessed Aug. 18, the closest genetic match to specimens Sci 26:135–50. 2016). collected from Laguna Beach were found Faleiro JR, Ben Abdullah A, El-Bellaj M, et al. 2012. Threat Hoddle MS. 2015. Red palm weevils – food or foe? Palms (Rugman-Jones et al. 2013). Second, low of red palm weevil, Rhynchophorus ferrugineus (Olivier) 59:21–31. to date palm plantations in North Africa. Arab J Plant Hoddle MS, Hoddle CD. 2011. Evaluation of three trap- genetic variability due to the small size of Prot 30:274–80. ping strategies for red palm weevil, Rhynchophorus fer- the founding population (Rugman-Jones Giblin-Davis R, Faleiro JR, Jacas JA, et al. 2013. Biology rugineus (Coleoptera: Curculionidae) in the Philippines. et al. 2013) may have reduced the fitness and management of the red palm weevil, Rhynchopho- Pak Entomol 33:77–80. rus ferrugineus. In: Peña JE (ed.). Potential Invasive Pests Hoddle MS, Hoddle CD. 2015. Evaluation of three trap- of the founding population. Third, the of Agricultural Crops. CABI Publishing, United Kingdom. ping strategies for the palm weevil, Rhynchophorus suitability of Phoenix spp. and other palm p 1–34. vulneratus (Coleoptera: Curculionidae) in Sumatra, Indo- species as hosts for R. vulneratus is not Hallett RH, Crespi BJ, Borden JH. 2004 Synonymy of nesia. Pak Entomol 27:73–7. Rhynchophorus ferrugineus (Olivier), 1790 and R. vul- known, and P. canariensis may be of mar- Ju R-T, Wang F, Wan F-H, Li B. 2011. Effect of host plant neratus (Panzer), 1798 (Coleoptera, Curculionidae, Rhyn- on the development and reproduction of Rhynchopho- ginal quality as a host. Collectively, when chophorinae). J Nat Hist 38:2863–82. rus ferrugineus (Olivier) (Coleoptera: Curculionidae). J coupled with targeted pesticide applica- Hallett RH, Gries G, Gries R, Borden JH. 1993. Aggrega- Pest Sci 84:33–9. tion pheromones of two Asian palm weevils, Rhyn- tions to infested palms, these factors may Liebhold AM, Tobin PC. 2008. Population ecology of in- chophorus ferrugineus and R. vulneratus. Naturwissen sect invasions and their management. Ann Rev Entomol have suppressed population growth and 80:328–31. 53:387–408. pushed weevil densities below the Allee Hoddle MS. 2010a. Confirmed: Live red palm weevil Longo S, Anderson PJ, Smith TR, et al. 2011. New palm found in U.S. http://cisr.ucr.edu/blog/invasive-species/ threshold, resulting in the extinction of hosts for the red palm weevil, Rhynchophorus ferrugin- confirmed-live-red-palm-weevil-found-in-us/ (accessed eus, in Sicily. Palms 55:15–20. this palm pest at Laguna Beach. c Aug. 18, 2016). Molet T, Roda AL, Jackson LD. 2011. CPHST Pest Data- Hoddle MS. 2010b. Red palm weevil technical working sheet for Rhynchophorus ferrugineus. USDA-APHIS- group field trip to Laguna Beach. http://cisr.ucr.edu/ PPQ-CPHST. Revised March 2014. www.aphis.usda.gov/ blog/invasive-species/red-palm-weevil-technical- plant_health/plant_pest_info/palmweevil/downloads/ working-group-field-trip-to-laguna-beach/ (accessed RedPalmWeevilFactsheet.pdf (accessed Aug. 18, 2016). M.S. Hoddle is UC Cooperative Extension (UCCE) Aug. 18, 2016). Murphy ST, Briscoe BR. 1999. The red palm weevil as an Specialist in Biological Control in the Department of Hoddle MS. 2010c. Informational meeting on new pest alien invasive: Biology and the prospects for biological Entomology and Director of the Center for Invasive in Orange County — red palm weevil. http://cisr.ucr. control as a component of IPM. Biocont News Inform Species Research at UC Riverside; C.D. Hoddle is Assistant edu/blog/uc-riverside/california-department-of-food- 20:35N–46N. and-agriculture-county-agricultural-commissioners- Specialist in the Department of Entomology at UC office/ (accessed Aug. 18, 2016). Pluess T, Cannon R, Pyšek P, et al. 2012. Which factors Riverside; M. Alzubaidy is Senior Environmental Scientist affect the success or failure of eradication campaigns Hoddle MS. 2010d. Red palm weevil infested palm at against alien species? PLoS One 7:e48157. at CDFA, Pest Detection/Emergency Projects, Anaheim; Laguna Beach removed. http://cisr.ucr.edu/blog/inva- J. Kabashima is UCCE Environmental Horticulture sive-species/red-palm-weevil-infested-palm-at-laguna- Rugman-Jones PF, Hoddle CD, Hoddle MS, Stouthamer beach-removed/ (accessed Aug. 18, 2016). R. 2013. The lesser of two weevils: Molecular genetics of Advisor Emeritus at South Coast Research and Extension pest palm weevil populations confirm Rhynchophorus Center, Irvine; J.N. Nisson is Entomologist at Orange Hoddle MS. 2011a. Palmageddon: Are California’s vulneratus (Panzer 1798) as a valid species distinct from County Agricultural Commissioner’s Office, Tustin; J. palms about to face the perfect storm? http://cisr. R. ferrugineus (Olivier 1790), and reveal the global ex- ucr.edu/blog/invasive-species/palmaggedon-are- tent of both. PLoS One 8(10):e78739. Millar is Professor of Entomology in the Department california%e2%80%99s-palms-about-to-face-the-per- of Entomology at UC Riverside; and M. Dimson is Staff fect-storm/ (accessed Aug. 18, 2016). Suckling DM, Tobin PC, McGullough DG, Herms DA. Research Associate at South Coast Research and 2012. Combining tactics to exploit Allee effects for Hoddle MS. 2011b. Red palm weevil outreach meet- eradication of alien insect populations. J Econ Entomol Extension Center, Irvine. ing in Coachella Valley. http://cisr.ucr.edu/blog/news/ 105:1–13. We are grateful to Duane Young, Cocopah red-palm-weevil-outreach-meeting-in-coachella-valley/ (accessed Aug. 18, 2016). Tobin PC, Kean JM, Suckling DM, et al. 2014. Determi- Nurseries, for donating date palms. Albert Keck and nants of successful arthropod eradication programs. Hadley Dates provided logistical support. We appreciate Hoddle MS. 2011c. Upcoming informational meeting on Invas Biol 16:401–14. the red palm weevil – El Centro, CA. http://cisr.ucr.edu/ the cooperation of homeowners in Laguna Beach blog/red-palm-weevil/upcoming-informational-meet- Turnbull K. 2004. Laguna Beach and South Laguna. who provided unrestricted access to their properties ing-on-the-red-palm-weevil-el-centro-ca/ (accessed In: Cramer E. A Hundred Years of Yesterdays II. Orange and cooperated with surveys, enhanced trapping Aug. 18, 2016). County Historical Commission. p 161–7. trials and pesticide treatments of infested palms. We Hoddle MS. 2011d. First move made against red palm Wattanapongsiri A. 1966. A revision of the genera Rhyn- chophorus and Dynamis (Coleoptera: Curculionidae). thank Kevin Hoffman, Laura Petro and Debby Tanouye weevil in Laguna Beach. http://cisr.ucr.edu/blog/inva- sive-species/first-move-made-against-red-palm-weevil- Dept Agric Sci Bull 1:1–328. (CDFA) and Helene Wright (USDA) for assistance. We in-laguna-beach/ (accessed Aug. 18, 2016). acknowledge the support of Marcie Johnson, Gilbert Vargas (arborist), West Coast Arborists, City of Laguna Beach, Target Specialty Products, Ed Black and RPW Services for assistance with surveys for infested palms Station (Lonsum) for their outstanding hospitality and in a commercial coconut plantation in the Philippines. and treating infestations. We are indebted to Stephen generous assistance with pheromone field evaluations Research in support of this project was supported, Nelson, Ahmed Saleh, Lisanti Cahyasiwi, Adi Sumantri, and aeration trials in Sumatra, Indonesia. We thank in part, by a CDFA Specialty Crops Grant, SCB11061, Linda Purwaninigsih and Prima Wijayanto, and Carmela Balcazar, of Villa Escudero Plantations, San “Addressing Urgent Research Needs for Red Palm Weevil also to Sumatra Bioscience and Bah Lias Research Pablo, Philippines, for facilitating pheromone field trials in California.”

http://calag.ucanr.edu • PUBLISHED ONLINE SEPTEMBER 8, 2016 7