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The birds of Tarquinia Salinas:
regional and local
determining factors
E.Lanzuisi1, M.Biondi2, J.Cecere3, G.Nascetti1 & G.Tallone3
1 DECOS Department, Tuscia University, Viterbo
2 GAROL, Rome
3 LIPU, Parma
Corresponding Author: Elisa Lanzuisi, [email protected]
(working hypotesis)
Study goals
1. Description of the Salina’s bird fauna
2. Analisis of temporal dynamics (year-
round cycle)
3. Historical trends
4. Local environmental factors - possible
correlations with species presence
5. Definition of management
prescriptions for the site
Tarquinia Salinas
•State Reserve from 1982
•Salt production ended in 1997
Description of the Salina’s bird fauna
Historical data analysis (bibliography
and non-published data)
Check-list of species recorded in the site
Quantitative description of the bird
species during year-round cicle
(migratory, overwintering and nesting
species)
Methods
Field surveys and complete count of
waterbirds only, counts every 10-15 days
[December 2004-April 2006] for the yearround cycle
Frequent winter counts (october-march),
every 15 days [2006-07 and 2007-08 winters]
Midwinter counts data (INFS-IWC) from 1982
to 2008 – mid January counts
Data for the winter 1975-6 published by
Allavena (1977)
Main determinants at regional scale
(working hypotesis)
Year round biological spatial dynamics
(migration, overwintering) at continental scale
(Europe, Mediterranean)
Wheather (Temperature, rainfall, …)
Sub-continental factors (“island effect”: wider
site, larger numers)
Main determinants at local scale
(working hypotesis)
Hyperaline “extreme” environment
Conspicuous gradient in salinity (from N to S)
Oxigen, pH
Water level
Water inputs: salt water from the sea, rain,
floodings during stormfalls
Trophic availability
Distrurbance (humans inside, planes, predation,
fast water level modifications)
1.Description of the Salina’s bird fauna
(nesting species)
(working hypotesis)
Nesting species (shorebirds)
Stilt – Cavaliere d’Italia
(Himantopus himantopus):
irregular breeding (not in the
study period)
Kentish plover - Fratino
(Charadrius alexandrinus):
irregular breeding (not in the
study period)
Little Ringed Plover - Corriere
piccolo (Charadrius dubius):
irregular breeding (not in the
study period)
Redshank - Pettegola (Tringa
totanus): possible breeding in the
past
Avoset – Avocetta
(Recurvirostra avocetta): attempt
to breed in 2007
Nesting species (waterbirds)
Shelduck - Volpoca (Tadorna
tadorna): one or two pairs, regular
breeding
Egret - Garzetta (Egretta
garzetta): nesting in a site nearly
the reserve with 20-30 pairs
Airone Guardabouoi (Bubulcus
ibis): first nesting in 2008;
Bee-eater - Gruccione (Merops
apiaster): nesting attempts in 2005
(aborted for disturbance), nesting
of a colony in 2006-7-8
Why so small success in nesting?
Small area, low idoneity
Disturbance from water level fast variation
Disturbance from predators (Gulls, dogs, rats, …)
Direct disturbance (humans inside for
management works, researchers, … example:
Merops apiaster colony attempt to breed)
2. Analisis of temporal dynamics
(year-round cycle)
(working hypotesis)
Results: Year-round cycle
Strong stagionality, typical in
Mediterranean wetlands, and especially
in salinas
Low number of breeding species
Maximum numbers in winter
(December-January)
Species richness (S) – for count
Species richness (S) – monthly average
Abundance (N) – monthly average
Abundance (N) – monthly average
•Different species
•Terns
•Gulls
•Shorebirds
•Gruiformes
•Anseriformes
•Greater Flamingo and
Spoonbill
•Herons, Egrets and Cormorants
•Grebes
3.Historical trends
(working hypotesis)
Results: Historical trends
(Overwintering birds)
Long historical series – IWC Counts
(from 1982)
Recent data during study (2004-2008)
Species richness and abundance
General trend: increasing in numbers
Abundance (N) – IWC Counts (January)
Trend: increasing
(For 1982-2008 series
R=0,643; F=16,921; p=0,0004)
N. max=2.742
•Different species
•Terns
•Gulls
•Shorebirds
•Gruiformes
•Anseriformes
•Greater Flamingo and
Spoonbill
•Herons, Egrets and
Cormorants
•Grebes
NB 1992 lack of data
Why an increasing?
Local factors: area legal protection from
1980, fence around the site from the
’80, more patrolling since half of ’90
Regional factors: increasing in numbers
after new hunting regulation in 1992
Carring capacity reached?
Site is quite
small
Some other large
site in the
sorrounding
Tyrrenian coastal
area (Burano,
Orbetello)
A size-number effect?
Area
Overwintering birds
2004
(IWC Counts, January)
Lago e Palude di Massaciuccoli
1907
1666
Diaccia Botrona, La Trappola e altre zone umide
grossetane
2048
26381
4179
20871
Saline di Tarquinia
149
2742
Macchiatonda
25
571
Litorale Romano
103
5296
Laghi Pontini
2200
20962
Lago di Fondi
702
1066
Tyrrenian wetland
Laguna di Orbetello e Lago di Burano
A size-number effect?
Tarquinia
R=0,72752078; R²= ,52928648; F(1,6 DoF)=6,7466; p<0,04080
4.Local environmental factors
(possible correlations with
species presence)
(working hypotesis)
Greater Flamingo - Fenicottero
(Phoenicopterus ruber)
-Filtratore iperspecialista
hypersaline environments
-General trend to increasing (R=
,72104457; R²=0,51990527; F con 1 e 25
gdl=27,073; p<,00002)
Common Teal - Alzavola
(Anas crecca)
- Mostly herbivorous
- General trend to increasing
R= 0,393; R²= 0,154; F con 1 e
25 DoF=4,5814; p<,04226)
Wigeon – Fischione (Anas
penelope)
- Mostly herbivorous
- A general trend for the whole
period doesn’t exist, but since
1987 a decreasing statistically
signifiant is present (R= 0,607;
R²= 0,369; F (1,20 DoF)=11,701;
p<,00271)
Coot – Folaga
(Fulica atra)
- Mostly herbivorous
- Constant, a peak in
2000, without any
signifiant trend
Dunlin - Piovanello
pancianera (Calidris
alpina)
- Feeding on invertebrates
in mud
- Trend to increasing
presence (R= 0,39353967;
R²=0,15487347; F (1, 25
DoF)=4,5814; p<,04226)
“Anatre” guild distribution
Concentred in ponds in
the north of the salinas,
with sea-like salinity and
deep water column
“Erbivori” guild distribution
Concentred in ponds in
the north of the salinas,
with sea-like salinity and
deep water column
“Filtratori” guild distribution
Distributed in near all
ponds, with different
salinity and
deep water column
“Gabbiani” guild distribution
Distributed in near all
ponds, with different
salinity and
deep water column,
but concentrated in
southern ponds
“Limicoli” guild distribution
Distributed in near all
ponds, with different
salinity and
deep water column,
but concentrated in
central and
southern ponds
Possible local determinants
Salinity
Water column deep
Oxigen
pH
Biomass (plancton, benthos)
First evidences
Guild
"Vasca" Var.
"Water column deep" Var.
Anatre - Ducks
F=14,86; p>0,00001
n.s.
Erbivori - Vegetarian
F=25,88; p>0,00001
n.s.
Filtratori - Filter feeders
F=13,542; p>0,00001
n.s.
Gabbiani - Gulls
F=4,14; p>0,000067
n.s.
Limicoli - Shorebirds
F=3,926; p>0,0001
F=2,6; p=0,0256
Piscivori - Fish eaters
F=19,27; p>0,00001
F=4,39; p=0,0008
Greater Flamingoes with markers
DATA
CODICE
COLORE
ANELLO
VERSO
LETTURA
TARSO
NOTE
9.1.2005
IDJC
Blu ?/Scritta bianca
28.7.2005
FLTP
Bianco
Dx
Anello metallico su zampa sx
13.10.2005
FSHA
Chiaro
Dx
Anello metallico piccolo su
zampa sx
13.10.2005
MPDT
18.11.2005
ITO
Scuro/scritta chiara
Sx
1.2.2006
FHXJ
Bianco
Dx
1.2.2006
FVAM
Giallo
Dx
1.2.2006
FSHA
Giallo chiaro
Dx
1.2.2006
FSBB
Giallo chiaro
1.2.2006
MLHD
Giallo
1.2.2006
1 | JTF
Giallo
Dx
1.2.2006
IFLZ
Verde/Scritta chiara
Dx
Sx
Anello metallico su zampa dx
Barra dopo prima cifra
5.Definition of management
prescriptions for the site
(working hypotesis)
Management prescriptions
Water level management for shorebirds
Mantaining salinity gradient
Avoiding disturbance (hides, access, …)
Creating islands for bird nesting
Developing birdwatching
Mantaining patrolling