THE SYNECOLOGICAL ANALYSE OF THE FALCONIFORMES SPECIES ACCORDING TO THEIR AERIAL ACTIVITY

Transcription

1 Analele Științifice ale Universității Al. I. Cuza Iași, s. Biologie animală, Tom LVII, 211 THE SYNECOLOGICAL ANALYSE OF THE FALCONIFORMES SPECIES ACCORDING TO THEIR AERIAL ACTIVITY Adrian MESTECĂNEANU 1 and Florin MESTECĂNEANU 2 1 Argeș County Museum, Armand Călinescu, 44, 1147, Pitești, Argeș, Romania, mestecaneanua@yahoo.com 2 Dârmănești, 11736, Argeș, Romania, mestecaneanuf@yahoo.com Abstract. In this paper, the authors present a part of the results regarding the research of the Falconiformes species observed on the wing between March 25 and February 28 on the Doamnei River hydrographic basin. 2 species were registered in order to their synecological analyse using the constancy, the dominancy, the Dzuba index of ecological significance, the Shannon-Wiener and Simpson diversities and the equitability. Keywords: Falconiformes, ecological indexes, Buteo buteo. Rezumat. In această lucrare, autorii prezintă o parte a rezultatelor privind studiul speciilor de falconiforme observate în zbor în perioada martie 25 februarie 28 în bazinul hidrografic Râul Doamnei. Au fost înregistrate 2 de specii, în vederea analizei sinecologice a acestora luându-se în calcul constanța, dominanța, indicele de semnificație ecologică Dzuba, diversitatea Shannon-Wiener și Simpson, precum și echitabilitatea. Cuvinte cheie: falconiforme, indici ecologici, Buteo buteo. Introduction Extended researches about the Falconiformes species from the Doamnei River hydrographic basin have not been done until now. There is only a single paper (Mătieș, 1974) regarding this, taking into account the situation of these birds between 1967 and 1973 in the Argeș County, including the area of this study. The author found 15 species: Falco tinnunculus (42.8% of all Falconiformes observed individuals) Buteo buteo (42%), Accipiter nisus (4,7%), Falco subbuteo (1.6%), Aquila chrysaetos (1.3%), Aquila pomarina (1.3%), Buteo lagopus (1.3%), Accipiter brevipes (.9%), Circus cyaneus (.7%), Accipiter gentilis (.5%), Falco vespertinus (.4%), Hieraetus pennatus (.4%), Circus aeruginosus (.2%), Falco peregrinus (.2%) and Milvus migrans (with.2%). Our research represents a part of a larger study about the birds that have a pronounced aerial activity, which mainly includes researches regarding the influence on flying of such factors as: hour, temperature, atmospheric nebulosity, type of clouds, force of the wind etc. Materials and Methods The Doamnei River is 19.1 km long and its hydrographic basin has 1822 km 2. The difference of level of 2284 m between the Moldoveanu Peak (2544 m) from the Făgăraș Massif and the point of confluence with the Argeș River (26 m) from the High Plain of Pitești (Barco & Nedelcu, 1974) offers a great diversity of relief and habitats favourable for the birds (Fig. 1). In this work, our purpose was to give an image about the relations established in every ecological season between the species of Falconiformes observed on flying during March 25 February 28 in the River Doamnei hydrographic basin and also about the hierarchy that are established. In this purpose we did their sinecologic analyze. Also, we evaluated the ecological diversity and the equitability

2 Adrian Mestecăneanu & Florin Mestecăneanu Figure 1. The hydrographic basin of the Doamnei River (modified by Barco & Nedelcu, 1974). - the zone limit. Results and Discussion 2 species of Falconiformes were identified: Aquila chrysaetos (.7% of all Falconiformes observed individuals), Aquila clanga (.8%), Aquila pomarina (1.41%), Circaetus gallicus (.2%), Buteo buteo (56.4%), Buteo lagopus (.1%), Pernis apivorus (8.87%), Accipiter gentilis (5.77), Accipiter nisus (14.32%), Milvus migrans (.5%), Pandion haliaetus (.2%), Circus aeruginosus (3.34%), Circus pygargus (.57%), Circus cyaneus (.35%), Circus macrourus (.2%), Falco subbuteo (4.43%), Falco columbarius (.8%), Falco vespertinus (1.78%), Falco naumanni (.5%) and Falco tinnunculus (2.17%). Their seasonal distribution: 7 species (35% from the whole number of the species observed) in the hiemal (Buteo buteo, Buteo lagopus, Accipiter gentilis, Accipiter nisus, Circus cyaneus, Falco columbarius and Falco tinnunculus), 17 species (85%) in the prevernal (Aquila clanga, Aquila pomarina, Circaetus gallicus, Buteo buteo, Buteo lagopus, Pernis apivorus, Accipiter gentilis, Accipiter nisus, Milvus migrans, Circus aeruginosus, Circus pygargus, Circus cyaneus, Circus macrourus, Falco subbuteo, Falco columbarius, Falco vespertinus and Falco

3 Hiemal Prevernal Vernal Estival Serotinal Autumnal Analele Științifice ale Universității Al. I. Cuza Iași, s. Biologie animală, Tom LVII, 211 tinnunculus), 12 species (6%) in the vernal (Aquila pomarina, Circaetus gallicus, Buteo buteo, Pernis apivorus, Accipiter gentilis, Accipiter nisus, Pandion haliaetus, Circus aeruginosus, Circus pygargus, Falco subbuteo, Falco vespertinus and Falco tinnunculus), 9 species (45%) in the aestival (Aquila chrysaetos, Aquila pomarina, Circaetus gallicus, Buteo buteo, Pernis apivorus, Accipiter gentilis, Accipiter nisus, Falco subbuteo and Falco tinnunculus), 13 species (65%) in the serotinal (Aquila chrysaetos, Aquila pomarina, Circaetus gallicus, Buteo buteo, Pernis apivorus, Accipiter gentilis, Accipiter nisus, Pandion haliaetus, Circus aeruginosus, Circus pygargus, Falco subbuteo, Falco vespertinus and Falco tinnunculus) and 16 species (8%) in the autumnal (Aquila chrysaetos, Aquila pomarina, Circaetus gallicus, Buteo buteo, Pernis apivorus, Accipiter gentilis, Accipiter nisus, Milvus migrans, Circus aeruginosus, Circus pygargus, Circus cyaneus, Falco subbuteo, Falco columbarius, Falco vespertinus, Falco naumanni and Falco tinnunculus). The ecological indicators used (conformable to the way of calculation) belong to two categories: analytical ecological indexes frequency (constancy), richness and dominance and synthetic ecological indexes Dzuba index of ecological signification (Gomoiu & Skolca, 21). According to the constancy, we noted that accidental species had the most weight each season. Their maximum was reached during migration, in the prevernal and autumnal s and the minimum in the hiemal and aestival s. The most numerous accessory species was recorded in the vernal and the least numerous in the autumnal one. The constant species had a minimum level from the autumnal season to the vernal one. It gradually augmented up to the serotinal season, when were registered the most of them. The euconstant species remained the same (one species from the hiemal season to the serotinal season), while in the autumnal season was attained the maximum of two species (Table 1, Fig. 2). Number of species Euconstant Constant Accesory Accidental Aspect Figure 2. The diagram of variation of the constancy categories by the ecological seasons. We observe that Buteo buteo was permanently euconstant species. Pernis apivorus was constant from the vernal season to the serotinal one, only in the prevernal and vernal s (at the beginning of the spring migration and at the ending of the autumn migration) being accidental species. Accipiter gentilis was mainly accessory species, in the aestival becoming accidental species and in the autumnal one, constant species. Falco subbuteo was accidental species in the prevernal and autumnal s, accessory in the vernal and aestival s, and constant in the serotinal one. The

4 Absolute frequency (no. of days with observations) Constancy Category of constancy Richness Dominance Category of dominance Index of ecological signification Dzuba Category of the index of ecological signification Dzuba Shanon-Wiener index Adrian Mestecăneanu & Florin Mestecăneanu other species (Aquila chrysaetos, Aquila clanga, Aquila pomarina, Circaetus gallicus, Buteo lagopus, Milvus migrans, Pandion haliaetus, Circus aeruginosus, Circus pygargus, Circus cyaneus, Circus macrourus, Falco columbarius, Falco vespertinus, Falco naumanni and Falco tinnunculus), when they were present, were accidental species (Table 1). Table 1. The ecological indexes of the observed Falconiformes species (in the EURING Code) in the Doamnei River hydrographic basin, according to the ecological seasons. Ecological indexes H(S)max Simpson Index (1/λ) S Species Hiemal Butbut C D W5 Butlag 1.38 C D1.1 W1 Accgen C D W3 Accnis C D W Circya C D2.34 W1 Falcol C D1.5 W1 Faltin C D1.2 W1 Prevernal Aqucla C D1.9 W1 Aqupom C D1.62 W1 Cirgal C D1.2 W1 Butbut C D W5 Perapi C D1.12 W1 Accgen C D W3 Accnis C D W4 Milmig C D1.3 W1 Ciraer C D3.444 W Cirpyg C D1.82 W1 Circya C D1.2 W1 Cirmac C D1.1 W1 Falsub C D1.38 W1 Falcol C D1.1 W1 Falves C D3.349 W2 Falnau C D1.4 W1 Faltin C D3.438 W2 Vernal Aqupom C D2.248 W2 Cirgal C D1.18 W1 Butbut C D W5 Perapi C D W4 Accgen C D3.937 W Accnis C D W3.23 Panhal 1.87 C D1.1 W1 Ciraer C D2.269 W2 Cirpyg C D2.91 W1 Falsub C D W3-84 -

5 Absolute frequency (no. of days with observations) Constancy Category of constancy Richness Dominance Category of dominance Index of ecological signification Dzuba Category of the index of ecological signification Dzuba Shanon-Wiener index Analele Științifice ale Universității Al. I. Cuza Iași, s. Biologie animală, Tom LVII, 211 Ecological indexes H(S)max Simpson Index (1/λ) S Species Falves C D4.937 W2 Faltin C D3.379 W2 Aestival Aquchr C D1.1 W1 Aqupom C D2.193 W2 Cirgal C D1.6 W1 Butbut C D W5 Perapi C D W Accgen C D3.587 W2 Accnis C D W4 Falsub C D W3 Faltin C D W3 Serotinal Aquchr C D1.2 W1 Aqupom C D3.44 W2 Cirgal C D1.2 W1 Butbut C D W5 Perapi C D W5 Accgen C D W3 Accnis C D W Panhal C D1.1 W1 Ciraer C D W3 Cirpyg C D1.79 W1 Falsub C D W3 Falves C D1.2 W1 Faltin C D2.145 W2 Autumnal Aquchr C D1.1 W1 Aqupom C D2.99 W1 Cirgal C D1.4 W1 Butbut C D W5 Perapi C D1.2 W1 Accgen C D W3 Accnis C D W5 Milmig C D1.1 W Ciraer C D4 1.2 W3.17 Cirpyg C D1.13 W1 Circya C D1.53 W1 Falsub C D3.758 W2 Falcol C D1.2 W1 Falves C D3.269 W2 Falnau C D1.1 W1 Faltin C D2.239 W2 Legend: C1, C2, C3, C4 categories of constancy, D1, D2, D3, D4, D5 categories of dominancy, W1, W2, W3, W4, W5 categories of index of ecological signification

6 Hiemal Prevernal Vernal Estival Serotinal Autumnal Adrian Mestecăneanu & Florin Mestecăneanu Regarding the dominancy, we remarked that the subrecedent species constituted almost twice the number of other species (in the prevernal season) and the same number (in the autumnal season), s when the main maximum and secondary maximum respectively of their curve of variation were reached. The minimum was recorded in the vernal and aestival s. The most recedent species was recorded in the vernal season and the least in the prevernal season ( species). Instead, in the prevernal season were observed the most subdominant species and the least in the hiemal season ( species). The maximum of the dominant species was in the vernal and serotinal s, the minimum being in the hiemal, prevernal and aestival s. Regarding to the eudominant species, the most numerous were registered in the aestival and serotinal seasons (3 species), in the rest of time, 2 species being present (Table 1, Fig. 3). Number of species Eudominant Dominant Subdominant Recedent Subrecedent Aspect Figure 3. The diagram of variation of the dominancy categories by the ecological seasons. Buteo buteo was always an eudominant species. Accipiter gentilis was a dominant species except in the vernal and aestival seasons when it was subdominant species. Accipiter nisus was generally eudominant species, only in the vernal season being dominant. Falco tinnunculus was subrecedent in the hiemal season, subdominant in the prevernal, vernal and aestival s, and recedent, in the serotinal and autumnal s. Among the species that were not found all the year in the area, Aquila pomarina was subrecedent in the prevernal season, recedent, in the vernal, aestival and autumnal ones, and subrecedent, in the serotinal one. Pernis apivorus was subrecedent species in the prevenal and autumnal s, in the rest of time ascending with Buteo buteo in the eudominant species category. Circus aeruinosus was subdominant species in the prevernal season and recedent species in vernal one, while in the serotinal and autumnal seasons was dominant species. Circus pygargus and Circus cyaneus, when present, were generally subrecedent species, the first being recedent in the vernal season and the second in hiemal one. After being a subrecedent species, Falco subbuteo remained from the vernal season to the serotinal one in the category of the dominant species; in the autumnal season it was subdominant species. Falco vespertinus, species present only in the passage, was dominant in the vernal season, subdominant in the prevernal and autumnal s and subrecedent, in the serotinal. Other species (Aquila chrysaetos, Aquila clanga, Circaetus gallicus, Buteo lagopus, Milvus migrans, Pandion haliaetus, Circus macrourus, Falco columbarius and Falco naumanni), when present, was constantly subrecedent. About the Dzuba index of ecological signification, we observed that, except the vernal and aestival seasons, the subrecedent species were the most numerous. Their maximum was in the prevernal and autumnal s and their minimum in the aestival

7 Hiemal Prevernal Vernal Estival Serotinal Autumnal Analele Științifice ale Universității Al. I. Cuza Iași, s. Biologie animală, Tom LVII, 211 season. In the hiemal season was not observed any species, in the aestival and serotinal seasons were observed two species of each of them, in the prevernal and autumnal seasons three species of each of them and in the venal season were observed the most (5 species). An interesting evolution had the subdominant species, which had a progressive increase from the hiemal season (1 species) to the serotinal one (3 species). A remarkable evolution had also the dominant species, during the prevernal season to the aestival season being one species and in rest of time, species. In the prevernal and vernal seasons, was only one eudominant species, in the hiemal, aestival and autumnal seasons were two species and in the serotinal season, three species (Table 1, Fig. 4) Number of species Eudominant Dominant Subdominant Recedent Subrecedent Aspect Figure 4. The diagram of variation of the Dzuba index categories by the ecological seasons. Buteo buteo was the only species eudominant in each ecological. Accipiter gentilis was subdominant species except the vernal and aestival s, when it was recedent species. Accipiter nisus was mainly an eudominant species, in the prevernal and aestival s being dominant species and, in the vernal, subdominant. Falco tinnunculus was, usually, recedent species, only in the hiemal being subrecdent and in the aestival one, subdominant species. Among the migratory species, Aquila pomarina was subrecedent species in the prevernal, recent species in the vernal, aestival and atumnal s and subrecedent species in the serotinal one. Pernis apivorus was subrecedent species in the prevernal and autumnal s, dominant in the vernal and eudominant species in the aestival and serotinal ones. Circus aeruginosus was recedent species in the prevernal and vernal s and subdominant species in serotinal and autumnal s. Falco subbuteo was subrecedent in the prevernal, recedent in the autumnal, and subdominant species from the vernal to the serotinal one. Excepting the serotinal, when it was subrecedent species, Falco vespertinus was recedent species. The other species (Aquila chrysaetos, Aquila clanga, Circaetus gallicus, Buteo lagopus, Milvus migrans, Pandion haliaetus, Circus pygargus, Circus cyaneus, Circus macrourus, Falco columbarius and Falco naumanni), when present, were subrecedent species. From the diversity point of view (Table 1, Fig. 5), the Shannon-Wiener index varied generally ascendantly from the hiemal season to the serotinal one. The index follows a sharp down from the serotinal season to the hiemal one. Alike is in the situation of the Simpson index, with the mention that the increasing (more pregnant and more linear) begins from the minimum level situated in the hiemal and prevernal s. For

8 Hiemal Prevernal Vernal Estival Serotinal Autumnal Adrian Mestecăneanu & Florin Mestecăneanu every index, the minimums correspond to the minimum stability and the maximums to the maximum stability of the Falconiformes community, the differences coming because the Shannon-Wiener index gives a bigger value for the rare species while the Simpson index gives a bigger value for the dominant species. Index value value Shanon-Wiever Index Simpson Index (1/λ) Shanon-Wiever equitability Simpson equitability Aspect Figure 5. The seasonal variation of the Shanon-Wiener and Simpson indexes and of the equitability. Regarding the equitability (Table 1, Fig. 5), it is an obvious similarity between the variation curves of the both calculated equitability. The minimums are placed each time in the prevernal and the maximums in the aestival and serotinal, for the Shannon-Wiener equitability, and in the aestival, for the Simpson equitability. So, the real diversity is the closest to the maximal one in the aestival season, when the Falconiformes population is more equilibrated from the point of view of the species number of individuals and it is the farthest in the prevernal, when the population is in an obvious disequilibrium because of great difference between the numbers of individuals of Buteo buteo and Accipiter nisus, on the one hand, and the other species on the other hand. Conclusions Between March 25 and February 28, by the method of flying birds observations, in the Doamnei River hydrographic basin, we found 2 species of Falconiformes (Aquila chrysaetos, Aquila clanga, Aquila pomarina, Circaetus gallicus, Buteo buteo, Buteo lagopus, Pernis apivorus, Accipiter gentilis, Accipiter nisus, Milvus migrans, Pandion haliaetus, Circus aeruginosus, Circus pygargus, Circus cyaneus, Circus macrourus, Falco subbuteo, Falco columbarius, Falco vespertinus, Falco naumanni and Falco tinnunculus), with 5 species more than Mătieș who recorded 15 species of birds (settled or on the wing) during , in the whole Argeș County. Eight new species was registered: Aquila clanga, Circaetus gallicus, Pernis apivorus, Pandion haliaetus, Circus pygargus, Circus macrourus, Falco columbarius and Falco naumanni, Pernis apivorus taking the most significance weight of them (8.87%). Three species were not found: Accipiter brevipes, Hieraetus pennatus and Falco peregrinus. The difference of percentage between the species observed in both studies reflects the dynamics of Falconiformes community, on the one hand, and the differentiation between the researched zones from the point of view of the habitats proportion, on the other hand. Also, it was influenced more or less by the two different used methods of study

9 Analele Științifice ale Universității Al. I. Cuza Iași, s. Biologie animală, Tom LVII, 211 According to the constancy, we noted that accidental species were preponderant each season. Instead, the euconstant species remained one species from the hiemal season to the serotinal season, in the autumnal season being attained the maximum of two species. Buteo buteo was permanently euconstant species. Regarding the dominancy, we remarked that the subrecedent species constituted almost twice the number of other species (in the prevernal season) and the same number (in the autumnal season). Relative to the eudominant species, the most numerous were registered in the aestival and serotinal seasons (3 species), in the rest of time, 2 species being present. Buteo buteo was always eudominant species. About the Dzuba index of ecological signification, we observed that, except the vernal and aestival seasons, the subrecedent species were, each time, the most numerous. Instead was only one eudominant species in the prevernal and vernal seasons, two species in the hiemal, aestival and autumnal seasons and three species in the serotinal season. Buteo buteo was again only eudominant species, each ecological. The Shannon-Wiener and Simpson diversities varied alike, with the minimums in the hiemal and prevernal seasons (when the stability was the most reduced), and with the maximums in the serotinal (when the stability was the highest). Regarding the equitability, the real diversity is the closest to the maximal one in the estival season, and the furthest in the prevernal. References Barco, A., Nedelcu, E., Județul Argeș. Editura Academiei Republicii Socialiste România, București. Gomoiu, M.T., Skolka, M., 21. Ecologie. Metodologii pentru studii ecologice. Ovidius University Press, Constanța. Mătieș, M., Contribuții privind cunoașterea situației actuale a păsărilor răpitoare de zi, ord. Falconiformes, din județul Argeș (perioada ). Nymphaea, Muzeul Țării Crișurilor, Oradea, II: