Rapid responses against invasive species on islands: lessons from the introduced Barbary ground squirrel Atlantoxerus getulus in the Canary Islands

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Rapid responses against invasive species on islands: lessons from the introduced Barbary ground squirrel Atlantoxerus getulus in the Canary Islands
Rapid responses against invasive species on islands:
                lessons from the introduced Barbary ground squirrel
                Atlantoxerus getulus in the Canary Islands
                                                     F É L I X M . M E D I N A , M A R T A L Ó P E Z - D A R I A S and J U L I E N C . P I Q U E T

                Abstract Despite efforts to combat invasive species, further                           increasing (Martín Esquivel et al., ) and the control of
                measures are still required to prevent their arrival and                               some of them entails severe financial costs (e.g. Lampropeltis
                translocation, especially into biodiverse island ecosystems.                           californiae; Gesplan, ). The archipelago lacks effective
                Although many governments worldwide have already estab-                                control, rapid warning procedures for invasive species, or
                lished protocols to control alien species, the European                                a legal framework to control movement of invasive species
                outermost regions have yet to implement fully effective                                between islands.
                prevention or rapid response procedures. The numerous                                      The invasive Barbary ground squirrel Atlantoxerus
                translocations of the invasive Barbary ground squirrel                                 getulus, which is native to Morocco and Algeria, illustrates
                Atlantoxerus getulus within the Canary Islands illustrate                              the situation. A pair of squirrels were taken to Fuerteventura
                this problem. From  to  at least . individuals                               in  as pets, and by the s the species had colonized
                per year have been moved from Fuerteventura to other is-                               most of the island (López-Darias, ). In Spain the species
                lands. If movements of these medium-sized vertebrates are                              is now legally considered an invasive species. Its possession,
                taking place regularly, the number of smaller species trans-                           commerce and transportation are banned, although it is still
                ported within the archipelago could potentially be greater.                            deliberately moved between islands. Here we review avail-
                We argue that it is essential to implement stricter strategies                         able data (from the scientific and grey literature, and per-
                for invasive species control in these remote biodiversity-rich                         sonal communications with reliable sources) on known
                islands, including early detection and rapid response, to                              translocations of the Barbary ground squirrel in the
                minimize impacts on native biodiversity.                                               Canary Islands, illustrating the lack of mechanisms pre-
                                                                                                       venting movement of invasive species within a European
                Keywords Alien species, Atlantoxerus getulus, Canary
                                                                                                       archipelago.
                islands, prevention, rapid response, squirrels
                                                                                                           From  to  there were at least  confirmed trans-
                                                                                                       locations (involving at least  individuals; Table , Fig. ) of
                Many governments have established guiding principles                                   Barbary ground squirrels between islands. An additional
                for the best cost-effective approach to counter problems                               seven sightings, two in , were not confirmed by knowl-
                posed by invasive species, and some countries have already                             edgeable individuals. There was no clear temporal pattern of
                developed rapid response strategies and early warning de-                              translocations (Fig. ), although they occurred in three per-
                tection programmes (FICMNEW, ; DEFRA, ;                                        iods: –, – and –. Most of the
                Genovesi et al., ). For the outermost territories of                               translocations (.%) were to Gran Canaria, probably
                Europe, European Regulation No. / on preventing                                because of its close commercial and touristic links with
                and managing invasive alien species, establishes that the                              Fuerteventura. Gran Canaria is a transit nexus for most of
                implementation of programmes is the responsibility of                                  the archipelago’s commercial routes, and well connected
                Member states. The regulation specifies that the require-                              (especially by sea) with Fuerteventura and Lanzarote. In
                ments to control invasive species should be more restrictive                           addition, Gran Canaria is the most populated island and
                in the outermost territories, and preventive measures or                               Fuerteventura is the main touristic island of the eastern
                rapid response procedures should be adapted to the specific                            Canaries, which increases the probability of squirrel translo-
                features of the territories. However, the regulation is only                           cations from Fuerteventura. Only a small number of trans-
                being partly enforced in many of these outermost territories.                          locations have been detected to Lanzarote, even though it
                In the Canary Islands the number of invasive species is                                is the closest island to Fuerteventura ( km distant).
                                                                                                       Lanzarote’s human population is six times less than that
                                                                                                       of Gran Canaria and, even though it is well connected to
                FÉLIX M. MEDINA (Corresponding author) Servicio de Medio Ambiente, Cabildo             Fuerteventura by sea, the ports are mainly resorts, with
                de La Palma, Avenida Los Indianos 20, 38700 Santa Cruz de La Palma, Canary             few resident islanders, and thus the likelihood of transloca-
                Islands, Spain. E-mail felix.medina@cablapalma.es
                                                                                                       tions is lower.
                MARTA LÓPEZ-DARIAS and JULIEN C. PIQUET Island Ecology and Evolution                       Considering the strict controls in place at airports, it is
                Research Group, Instituto de Productos Naturales y Agrobiología, Consejo
                Superior de Investigaciones Científicas, Tenerife, Canary Islands, Spain               most likely that squirrels are moved by sea. As the keeping
                Received  October . Revision requested  January .                            of squirrels is illegal, it is unlikely that escapes will be re-
                Accepted  January . First published online  May .                          ported by owners to the relevant authorities. On only one

                                                                                           Oryx, 2019, 53(4), 782–786 © 2018 Fauna & Flora International doi:10.1017/S0030605318000200
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https://doi.org/10.1017/S0030605318000200
https://doi.org/10.1017/S0030605318000200
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                                                                                                                                                                                                      Oryx, 2019, 53(4), 782–786 © 2018 Fauna & Flora International doi:10.1017/S0030605318000200

                                                                                                                                                                                                                                                                                                    TABLE 1 All known confirmed and unconfirmed translocations of the Barbary ground squirrel Atlantoxerus getulus from Fuerteventura to elsewhere in the Canary Islands (see ID numbers in
                                                                                                                                                                                                                                                                                                    Fig. ) during –, with date of detection or capture if known.

                                                                                                                                                                                                                                                                                                                                 Date of
                                                                                                                                                                                                                                                                                                              Year of            detection/                                                                        No. of            Other
                                                                                                                                                                                                                                                                                                    ID        introduction       capture              Location                                Island               individuals       information                   Source
                                                                                                                                                                                                                                                                                                    Confirmed translocations
                                                                                                                                                                                                                                                                                                    1       1996                                      La Isleta                               Gran Canaria         1                 Euthanized                     Calabuig (1999)
                                                                                                                                                                                                                                                                                                    2       1997                                      San Fernando de Maspalomas              Gran Canaria         1                 Euthanized                     Calabuig (1999)
                                                                                                                                                                                                                                                                                                    3       1997                                      Lomo Blanco, Las Palmas de              Gran Canaria         1                 Euthanized                     Calabuig (1999)
                                                                                                                                                                                                                                                                                                                                                      Gran Canaria
                                                                                                                                                                                                                                                                                                    4         1997                                    Telde                                   Gran Canaria         2                 Euthanized                     Calabuig (1999)
                                                                                                                                                                                                                                                                                                    5         1997                                    Cuatro Puertas, Telde                   Gran Canaria         1                 Euthanized                     Calabuig (1999)
                                                                                                                                                                                                                                                                                                    6         1997                                    Las Palmas de Gran Canaria              Gran Canaria         1                 Euthanized                     Calabuig (1999)
                                                                                                                                                                                                                                                                                                    7         1997                                    Monte Lentiscal, Tafira                 Gran Canaria         2                 Euthanized                     Calabuig (1999)
                                                                                                                                                                                                                                                                                                    8         1998                                    Barranco de Guayadeque                  Gran Canaria         5                 Shot or trapped                Calabuig (1999)
                                                                                                                                                                                                                                                                                                    9         1998               9 Aug. 1998          La Lechuza, Vega de San Mateo           Gran Canaria         1                 Castrated & kept in            Calabuig (1999)
                                                                                                                                                                                                                                                                                                                                                                                                                                     captivity in CRFS
                                                                                                                                                                                                                                                                                                                                                                                                                                     Tafira
                                                                                                                                                                                                                                                                                                    10        1998               30 Aug. 1998         Cortijo de Pajonales                    Gran Canaria         1                 Shot                           Calabuig (1999)
                                                                                                                                                                                                                                                                                                    11        2006               8 Nov. 2006          El Cable, Arrecife                      Lanzarote            1                 Trapped                        Authors’ data
                                                                                                                                                                                                                                                                                                    12        2006               13 Nov. 2006         El Cable, Arrecife                      Lanzarote            1                 Trapped                        Authors’ data
                                                                                                                                                                                                                                                                                                    13        2007               1 Feb. 2007          Unspecified                             Gran Canaria         1                 Trapped                        Fundación Neotrópico,
                                                                                                                                                                                                                                                                                                                                                                                                                                                                    pers. comm.
                                                                                                                                                                                                                                                                                                    14        2007               30 Aug. 2007         Unspecified                             Gran Canaria         1                 Trapped                        Fundación Neotrópico,
                                                                                                                                                                                                                                                                                                                                                                                                                                                                    pers. comm.
                                                                                                                                                                                                                                                                                                    15        2007               5 Nov. 2007          Unspecified                             Gran Canaria         2                 Trapped                        Fundación Neotrópico,
                                                                                                                                                                                                                                                                                                                                                                                                                                                                    pers. comm.
                                                                                                                                                                                                                                                                                                    16        2009               17 Apr. 2009         Batería de San Juan, Las Palmas         Gran Canaria         1                 Trapped                        Fundación Neotrópico,
                                                                                                                                                                                                                                                                                                                                                      de Gran Canaria                                                                                               pers. comm.
                                                                                                                                                                                                                                                                                                    17        2014                                    Muelle de Santa Cruz de Tenerife        Tenerife             1                 Confiscated because il-        Fundación Neotrópico,
                                                                                                                                                                                                                                                                                                                                                                                                                                     legally transported            pers. comm.
                                                                                                                                                                                                                                                                                                    18        2014                                    La Lomada Grande, Garafía               La Palma             1                 Euthanized                     Authors’ data
                                                                                                                                                                                                                                                                                                    19        2015               2 Aug. 2015          Punta Gaviota, Vecindario               Gran Canaria         1                 Photographed but               Social network
                                                                                                                                                                                                                                                                                                                                                                                                                                     never trapped or later         announcement

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              Invasive species on islands
                                                                                                                                                                                                                                                                                                                                                                                                                                     seen
                                                                                                                                                                                                                                                                                                    20        2015               5 Oct. 2015          El Burrero, Ingenio                     Gran Canaria         1                 Photographed but               Social network
                                                                                                                                                                                                                                                                                                                                                                                                                                     never trapped or later         announcement
                                                                                                                                                                                                                                                                                                                                                                                                                                     seen
                                                                                                                                                                                                                                                                                                    21        2016               1 Sep. 2016          Punta de Gando, Telde                   Gran Canaria         1                 Trapped & euthanized           Authors’ data
                                                                                                                                                                                                                                                                                                    22        2016               15 Nov. 2016         Juncalillo del Sur, San Bartolomé       Gran Canaria         1                 Found as remains               A. Padrón, unpubl.
                                                                                                                                                                                                                                                                                                                                                      de Tirajana                                                                                                   data
                                                                                                                                                                                                                                                                                                    23        2016                                    Santa Cruz de Tenerife                  Tenerife             1                 Trapped                        Fundación Neotrópico,
                                                                                                                                                                                                                                                                                                                                                                                                                                                                    pers. comm.

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              783
784         F. M. Medina et al.

                                                                      J. L. Rodríguez-Luengo
                                                                      S. Martín, pers. comm.
                                                                      H. López, pers. comm.

                                                                      S. de la Cruz, unpubl.

                                                                      R. Gallo, pers. comm.
                                                                      G. González, pers.

                                                                      N. Migraine, pers.

                                                                      & B. Fariña, pers.
                                                                      comm.

                                                                      comm.

                                                                      comm.
                                         Source

                                                                      data
                                                                                                                                              FIG. 1 The Canary Islands, showing the locations of all
                                         information

                                                                                                                                              confirmed translocations of Barbary ground squirrels
                                                                                                                                              Atlantoxerus getulus during –. Numbers correspond to
                                         Other

                                                                                                                                              the ID in Table . White numbers represent the total number of
                                                                                                                                              squirrels translocated to each island.

                                                                                                                                              occasion (ID , Table ) was a squirrel confiscated at a port,
                                         individuals

                                                                                                                                              which demonstrates the laxity of control measures. As all
                                         No. of

                                                                                                                                              the islands in the archipelago are climatically suitable for
                                                                                                                                              the Barbary ground squirrel (López-Darias et al., ),
                                                                      1

                                                                                     1
                                                                                     1
                                                                                     1

                                                                                                      1

                                                                                                                    1
                                                                                                                    1

                                                                                                                                              the invasion of other islands is only a matter of time unless
                                                                                                                                              effective procedures are applied.
                                                                      Gran Canaria

                                                                                     Gran Canaria
                                                                                     Gran Canaria
                                                                                     Gran Canaria

                                                                                                                    Gran Canaria

                                                                                                                                                  When a squirrel is reported on islands other than
                                                                                                      La Graciosa

                                                                                                                                              Fuerteventura the relevant government body has to take ac-
                                                                                                                    Tenerife
                                         Island

                                                                                                                                              tions that require both financial and human resources not
                                                                                                                                              specifically intended for the purpose. As there is no coordi-
                                                                                                                                              nated response protocol, each public administration tackles
                                                                                                                                              each detected translocation independently. In  La
                                                                                                                                              Palma insular government captured an introduced squirrel
                                                                                                                                              shortly after its initial sighting, requiring  h of trapping
                                                                                                                                              and c. EUR , (ID , Table ). On Gran Canaria, after
                                                                                                                                              failed attempts by the island government to capture two
                                                                                                                                              squirrels introduced in , external professionals were
                                                                                     Cuevas Blancas

                                                                                                                                              subcontracted by the regional authorities (at a cost of EUR
                                                                                                                    Punta Prieta

                                                                                                                                              ,) almost  year after the original sighting. Following
                                                                                     El Confital

                                                                                                                    San Mateo
                                                                                     Los Giles
                                         Location

                                                                                                                                               hours of observation,  questionnaires collected from
                                                                      Amagro
                                         detection/
                                         capture
                                         Date of

                                                        Unconfirmed translocations
                                         introduction

                                                                2015–2016

                                                                                     2015–2016
                                                                                     2015–2016
                                                                                     2015–2016
                                         Year of
                       Table 1 (Cont.)

                                                                                                      2016

                                                                                                                    2017
                                                                                                                    2017

                                                                                                                                              FIG. 2 Number of known, confirmed translocations of Barbary
                                                                                                                                              ground squirrels within the Canary Islands per year from  to
                                                                                                                                              . Gaps between years indicate that no translocations were
                                         ID

                                                                                                                                              detected.

                                                                                                                                   Oryx, 2019, 53(4), 782–786 © 2018 Fauna & Flora International doi:10.1017/S0030605318000200
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https://doi.org/10.1017/S0030605318000200
Invasive species on islands                785

              the local inhabitants,  ha searched and  h of trapping,                            translocated squirrels. MLD is funded by the Program Agustín de
              they captured one squirrel (ID , Table ).                                           Betancourt, under the identification Tenerife  (P. INNOVA
                                                                                                     -). JCP is funded by a Canary Islands Government PhD
                  The case of the Barbary ground squirrel is only one ex-
                                                                                                     fellowship.
              ample of the permeability of the sea barriers within this
              archipelago. If larger animals can be translocated between
              islands (e.g. the mouflon Ovis orientalis; Acevedo-
              Rodríguez & Medina, ), it is probably relatively easy                              Author contributions
              to translocate smaller animal species and plants. The costs                            All authors contributed equally to this research and article.
              of removing invasive species in the whole archipelago are
              unknown (controlling alien invertebrates on La Palma has
              been estimated to cost . EUR  million per year; García-
                                                                                                     References
              Becerra & Medina, ). Removing naturalized invasive
              species is more expensive than preventing their introduction                           A C E V E D O -R O D R Í G U E Z , A. & M E D I N A , F.M. () Sobre la presencia
              (Pimentel et al., ). EU Regulation No. / states                                del muflón (Ovis orientalis Gmelin, ) en la isla de La Palma
              that no later than January  all nations should have                                    (Archipiélago Canario). Galemys, , –.
              fully operational structures for preventing and controlling                            C A L A B U I G , P. () Informe sobre las actuaciones realizadas
                                                                                                         para controlar la incipiente población de ardilla moruna
              the entry of invasive species. However, the implementation                                 (Atlantoxerus getulus) en la isla de Gran Canaria. Unpublished
              of those rules is delayed in the Canary Islands.                                           report. Área de Medio Ambiente, Cabildo de Gran Canaria, Canary
                  European outermost regions require an early warning                                    Islands, Spain.
              and rapid response system, as implemented in New                                       DEFRA () The invasive non-native species framework strategy for
              Zealand, Australia and Hawaii (e.g. Simberloff et al., ),                              Great Britain. Department for Environment, Food and Rural
                                                                                                         Affairs, London, UK.
              to prevent further introductions and translocations of spe-
                                                                                                     FICMNEW () A National Early Detection and Rapid Response
              cies already established in other regions. The creation of                                 System for Invasive Plants in the United States. Federal Interagency
              such a system, involving governments, decision makers, ex-                                 Committee for the Management of Noxious and Exotic Weeds,
              perts, NGOs, and other appropriate stakeholders (Simpson                                   Washington, DC, USA.
              et al., ), is a conservation priority for the Canary Islands                       G A R C Í A -B E C E R R A , R. & M E D I N A , F.M. () Impedir la entrada
                                                                                                         siempre es más económico que controlar o erradicar. Agropalca,
              and other biodiverse island territories. In July  a pilot
                                                                                                         , .
              trial was approved by the Canary Government for an inva-                               G E N OV E S I , P., S C A L E R A , R., B R U N E L , S., R O Y , D. & S O L A R Z , W. ()
              sive species detection and intervention network (Gobierno                                  Towards an Early Warning and Information System for Invasive
              de Canarias, ). The information summarized here has                                    Alien Species (IAS) Threatening Biodiversity in Europe. European
              been shared with the public administration of the various                                  Environment Agency Technical report No. /, Copenhagen,
              islands and with other stakeholders, to encourage imple-                                   Denmark.
                                                                                                     G E S P L A N () Control of the invasive species Lampropeltis getula
              mentation of appropriate control mechanisms, and our re-                                   californiae on the island of Gran Canaria. Http://www.
              commendations have been passed via internal reports and                                    lifelampropeltis.com/images/pdf/D_EN_Informe_Layman__.
              personal communications to the Canarian authorities,                                       pdf [accessed  January ].
              both at insular and regional level.                                                    G O B I E R N O D E C A N A R I A S () Orden de  de julio de , por la que
                  Within the Canary Islands there have not yet been any                                  se encomienda a la empresa pública Gestión y Planeamiento
                                                                                                         Territorial y Medioambiental, S.A. (GESPLAN) el servicio
              public education campaigns to communicate the problems                                     denominado ‘Red de Detección e Intervención de Especies Exóticas
              of invasive species. In the case of the Barbary ground squir-                              Invasoras en Canarias. Experiencia piloto’. Http://www.gobcan.es/
              rel the only action taken to prevent its transportation to                                 boc///.html [accessed  January ].
              other islands was to place information plaques at airports                             L Ó P E Z -D A R I A S , M. () Ecología de una invasión: el caso de la
              and ports in the s, but these only remained in place                                   ardilla moruna (Atlantoxerus getulus) en la isla de Fuerteventura.
                                                                                                         PhD thesis. Estación Biológica de Doñana and Universidad de La
              for a few years. In addition to detection and intervention,
                                                                                                         Laguna, La Laguna, Spain.
              a public education programme is required, to inform society                            L Ó P E Z -D A R I A S , M., L O B O , J.M. & G O U AT , P. () Predicting
              about the risks related to invasive species.                                               potential distributions of invasive species: the exotic Barbary ground
                                                                                                         squirrel in the Canarian archipelago and the west Mediterranean
                                                                                                         region. Biological Invasions, , –.
              Acknowledgements                                                                       M A R T Í N E S Q U I V E L , J.L., M A R R E R O G Ó M E Z , M.C., Z U R I T A , N.,
                                                                                                         A R E C H AVA L E T A , M. & I Z Q U I E R D O Z A M O R A , I. ()
              Segundo Lorenzo and Ángel M. Mallorquín helped us in the field in La                       Biodiversidad en gráficas. Especies silvestres de las Islas Canarias.
              Palma. Aurelio Martín and Juan Luis Rodríguez-Luengo revised a first                       Consejería de Medio Ambiente y Ordenación Territorial, Gobierno
              draft and provided useful data. Fundación Neotrópico, Guillermo                            de Canarias, Spain.
              Delgado, Salvador de la Cruz, Susana Saavedra, Jeremías Cabrera,                       P I M E N T E L , D., L AC H , L., Z U N I G A , R. & M O R R I S O N , D. ()
              Guillermo González, Beatriz Fariña, Nancia Migraine, Sonia Martín,                         Environmental and economic costs associated with non-indigenous
              Heriberto López and Ramón Gallo provided information about                                 species in the United States. BioScience, , –.

              Oryx, 2019, 53(4), 782–786 © 2018 Fauna & Flora International doi:10.1017/S0030605318000200
Downloaded from https://www.cambridge.org/core. IP address: 46.4.80.155, on 06 Nov 2021 at 23:48:48, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms.
https://doi.org/10.1017/S0030605318000200
786         F. M. Medina et al.

                S I M B E R LO F F , D., M A R T I N , J.-L., G E N O V E S I , P., M A R I S , V., W A R D L E ,    Biographical sketches
                    D.A., A R O N S O N , J. et al. () Impacts of biological invasions:
                    what’s what and the way forward. Trends in Ecology & Evolution, ,                              F É L I X M . M E D I N A studies the trophic feeding ecology of feral cats
                    –.                                                                                           and their impacts on native species on islands, and he is interested
                S I M P S O N , A., J A R N E V I C H , C., M A D S E N , J., W E S T B R O O K S , R.,              in the effects of introduced species on the conservation of island eco-
                    F O U R N I E R , C., M E H R H O F F , L. et al. () Invasive species                        systems. M A R T A L Ó P E Z - D A R I A S ’ S research is mainly focused on the
                    information networks: collaboration at multiple scales for                                       ecology, impacts and management of invasive vertebrate species on is-
                    prevention, early detection, and rapid response to invasive alien                                lands, particularly on the Canary Islands. J U L I E N C . P I Q U E T ’ S re-
                    species. Biodiversity, , –.                                                                 search is mainly focused on invasive species and their impact on
                                                                                                                     insular biodiversity and ecological and evolutionary processes.

                                                                                                          Oryx, 2019, 53(4), 782–786 © 2018 Fauna & Flora International doi:10.1017/S0030605318000200
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https://doi.org/10.1017/S0030605318000200
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