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Antoine Chabrolle,Recovery Action Plan Coordinator

Caribaea initiative 2016

Predation on nesting sea turtlesby small Indian Mongoose in

Guadeloupe

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Small Indian MongooseBiology

Urva auropunctata

Mongoose are omnivore (crabs, rats, fruits, birds, invertebrates, Herpetophauna)

Mean of 2.2 embryos, with a range of 1 to 5

The youngest wild-caught pregnant female with a confidently estimated age (determined by mass of the eye lens) was 4 months old

Average density of 5 individuals mongooses per hectare, including all the major islands of the world where it has been introduced

Native range in southern Asia

Small Carnivore mammal

Body lenght : 500 à 650 mm (with tail)Body mass : 435 g for adultes

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Small Indian Mongoosein Caraibes

This species now occurs on islands or mainlandselsewhere in Asia, Africa, Europe, North America, South America, and Oceania.

In 1872, a sugar planter introduced four male and five female small Indian mongooses to Jamaica from eastern India (Espeut 1882).

From Jamaica, mongooses eventually were introduced to 29 islands throughout the Caribbean and also to the northern coast of South America

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Guadeloupe is Frenck West Indies

Guadeloupe location

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Sea turtlesin Guadeloupe

233 activities

637 activities

1 908 activities

Nesting activity in 2014

+ 150 nesting beachs

Protection : > Guadeloupe : since 1991

> Recovery action about sea turtles in French West Indies (since 2006)

Survey : > NGO : since 1999

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Small Indian Mongoose in Guadeloupe

Urva auropunctata

Small Carnivore mammalSize : 50 à 65 centimètres (with tail)Weight : 435 g for adultes

Historical :The mongoose was introduced to Guadeloupe in 1888 to control rats in cane-field

Classification:Invasive Exotic species in GuadeloupeBetwen 100 species most invasive in world

=> now threatens the native fauna

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Mongoose in Guadeloupefirst impact on sea turtles

impact on sea turtles :1991, first impact on nestingHawkasbill turtle

1998-2000 : May be 90 % nesting are affected

104 ha of mangrove on peat,

11 ha of dryvegetation on sandy

soil

Fajou Island

Eradicate plan:2001, simultaneously by trapping and chemical baits an attempt was done to eradicate the Javanese Mongoose(Herpestes javanicus), the Ship Rat (Rattus rattus) and the House Mouse (Mus domesticus)

=> 76 mongooses were killed

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Mongoose in GuadeloupeNews impacts

Nesting beachs

Mongoose predation since 2013

Mongoose predation since 2014

Increase of impact

Specialy on Hawkasbill nesting beachs

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Mongoose in GuadeloupeImpacts analisys & contrôle - 2015

Cyril Cottaz

Student of Master 1 Management and Biodiversity ConservationBritany University in France

Action plan

Axis 1: Identification of nesting activities, understanding of the predation strategy mongoose and impact assessment(June – August 2015)

Axis 2: Nests protection (July – August 2015)

Axis 3: Eradication of the threat (August 2015)

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Protocol axis 1

Axis 1 : Identification of nesting activities, understanding of the predation strategy mongoose and impact assessment (June – August 2015)

Identification all nests with tag Nests predation control

Use to camera

Control the nest after "emergence"

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Axis 2 : Protection of nests (July - August 2015)

Plastic Grids(50 cm x 50 cm)

-On the recent nesting area well identified

-On the nesting area after the first predetion for the other nests

The grids are removed 5 days before the estimated output of baby turtles

Repellent egg with hot pepper

-On nesting area after the first predation-Uniformly over the linear range of the beach

Protocol axis 2

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Axis 3 : Eradication of the threat (August 2015)

Estimate density

Placing trap

-20 taps

-check twice daily

Protocol axis 3

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Results axis 1

Mongoose is a diurnal predatorSeveral individuals share the same territoryMongooses seek their own food, except for the very youngThe eggs are eaten locally but are also transported awaySeveral mongooses may alternatively prédater same nestThe mongoose attacks the nests predominantly 0-3 days after laying, and just before the release of hatchlings

Up to 92% of predated nestsAbout 30 predated eggs per nest (2800 eggs eaten in the study area in three months)Route of entry for other predatorsMore eggs infertile by predated nests, probably related to environmental disturbances eggs

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Results axis 2

Plastic Grids

Help to limit cases of predation or predation againNew predation on nest when the grids are removedDo not prevent cases of predation on hatchlings

Repellent egg with hot pepper

They eat the eggs with hot peppers.=>This technique doesn’t works.

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Results axis 3

37 mangooses trapped

decrease predation rate x3 on the nests between June and August (92 to 29 %)

No predation in September on the sector with placement of traps

Observationof traces of rats on the beach

=> this technique is effective

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To conclude

Mongooses are a real threat to sea turtle nesting

92% of nest impact without protection

Predation is currently limited to a few beaches

Need to act quickly

Trapping seems a effective technique