POPULATION TRENDS OF THE COMMON ( coturnix) IN FRANCE AND SPAIN: CONFLICTING DATA OR CONTROVERSIAL CENSUS METHODOLOGIES?

Puigcerver, M.1, Eraud, C.2, García-Galea, E.1, Roux, D.2,Jiménez-Blasco, I1, Sarasa, M.3 & Rodríguez-Teijeiro, J.D.1

1. Universitat de Barcelona, Spain. 2. Office National de la Chasse et de la Faune Sauvage, France. 3. Fédération Nationale des Chasseurs, France. SOME FEATURES OF THE COMMON QUAIL

• Migratory and nomadic species. • Current conservation status: Least Concern (BirdLife International 2017). • Population trend: it appears to be decreasing (Birdlife International 2017). • It is very difficult to census (Gregory et al. 2005, Phil. Trans. R. Soc. B 360: 269-288 ).

• It is a huntable species in some Mediterranean countries.

Source of controversy between hunters, conservationists and wildlife managers TRYING TO CLARIFY POPULATION TRENDS

• Census in: • Four breeding sites of France (2006-2016). • Two breeding sites of NE Spain (1992-2016).

ACTIVE METHOD

• The whole France (1996-2016), ACT method. • Prats, NE Spain (2002-2016), SOCC method.

PASSIVE METHOD -Prats ACTIVE METHOD Vs PASSIVE METHOD

ACTIVE METHOD: PASSIVE METHOD (ACT SURVEY): • It counts males responding to a • It counts only males singing digital female decoy. spontaneously. • 10 count points spaced by at • 5 point counts spaced by 1km. least 700 m. • Based in just one day throughout • Once a week throughout the the breeding season. breeding season. • It has a general design for 17 • Specific design for the Common breeding species. quail. • Large-scale survey (the whole • Local scale survey (2-4 breeding France) sites)

INTENSIVE BUT LOCAL METHOD WEAK BUT WIDESPREAD METHOD PASSIVE METHOD

PASSIVE METHOD (ACT SURVEY): PASSIVE METHOD (SOCC) • Only data from mid-May to mid- • 6 count points spaced by 500 m. June was analysed. • All the species detected are censused. • Counts performed outside a • Data from two days (one presumed window of availability between 15th April-15th May were discarded. and another between 15th May- • Routes where Common 15th June). were never detected since 1996 • Second census must be done at were discarded. least 15 days later. • Routes surveyed less than 10 years • Census in good meteorological conditions. were also discarded. • From sunrise to next 4 hours. ANALYSES

• Generalised Additive Mixed Models with poptrend R-Package.

• Active method data: • Quasi-Poisson error distribution and log link function. • Number of detected males: response variable. • “Date” and “Site”: factors. • “Year”: covariate and random factor.

• Passive method data: • Negative binomial distribution. • Number of detected males: response variable. • “Year”, “Date” and “Counting hours”: covariates. • “Site” and “Year”: random factors. ACTIVE METHOD-Vs PASSIVE METHOD (I)

Catalonia, NE Spain (Alp and The whole France (ACT survey) Figuerola del Camp) ACTIVE METHOD Vs PASSIVE METHOD (II)

France (Montbel, La Cavalerie, Sault and Time window: 2006-2016. Space L’Ariège) window: 1-6.3 degrees longitude East and South of 44 degrees North. THESE RESULTS GENERATE SOME DOUBTS

Are Common quail stable in Catalonia but declining in France?

Are the differences found in our results due to the different census methods applied?

Am I decreasing or am A more exhaustive analysis is needed! I stable???? IN THE 21-YEARS PERIOD OF ACT SURVEY IN THE WHOLE FRANCE…

In most sites and years there are no quails or there are very few ones DIVIDING THE DATA SET BY ABUNDANCE…

Places in which quails have Places in which quails have Places in which quails have been detected from 1 to 7 been detected from 8 to 14 been detected from 15 to times in 21 years times in 21 years 21 times in 21 years

Bad quail habitats Bad-intermediate habitats Good habitats PASSIVE METHOD

Relationship between the total counts in a given Relationship between the probability of place and the probability of at least one detection and the mean count when there is at detection (number of years from the total 21- least one detection. years period that quails are detected in one site).

COMPATIBLE WITH A DENSO-DEPENDENCE SCENARIO ACTIVE AND PASSIVE METHODS MAY NOT CENSUS THE SAME THINGS

Population trend in Prats Population trends in Alp Relationship between (passive method) (active method) Prats census and Alp census

When there are 3 quails or less, Catalan passive method censuses zero individuals CONCLUSIONS

• In good habitat sites of Catalonia (NE Spain), by using an active census method, no trends have been observed. • In the whole France, by using a passive method, a decreasing trend has been observed. • However, in good French habitat sites for the Common quail, no trends are observed. • Results obtained when using the passive method in France are compatible with a scenario of denso-dependence. • It may provoque a lack of detectability when quail abundance is low. • Active and passive methods could be unrelated. • These results strongly suggest that more studies (i.e. INLA analyses) must be carried out in the near future, in order to inequivocally determine the Common quail population trends in France. THANK YOU VERY MUCH FOR YOUR ATTENTION!