STUDIES ON THE COMPARATIVE ECOLOGY OF THE SOUTH PERSIAN BLACK PARTRIDGE, FRANCOLINUS FRANCOLINUS HENRICI, AND THE NORTHERN GREY PARTRIDGE, FRANCOLINUS PONDICERIANUS INTERPOSITUS, IN LAL SUHANRA NATIONAL PARK, BAHAWALPUR, PUNJAB, PAKISTAN

Abstract

Transect data collected on sympatric population of the two species of Francolins from 23 strands established in Lal Suhanra National Park (LSNP) suggested that the South Persian Black Francolin (Francolinus francolinus henrici) was present in 6 and the Northern Grey Francolin (Francolinus pondicerianus interpositus) from 10 stands. The density figures developed from the calls and sightings revealed a variation in the estimated during different seasons and parts of the day, but its variation were much wider from calls. Call count technique appeared on yield reliable densities if carried out during winter and sighting data can reliably used if carried out simultaneously during the morning and the evening sessions. The Black Francolin was distributed with an overall crude density 8.40±1.39 birds per km2, while the Grey Francolin with a crude density of 6.20±1.52 birds per km2. The population density of the Black Francolin was lowest in February (3.03±1.09 birds per km2) and the highest in July (7.28±1.72 birds per km2). The lowest density of the Grey Francolin was in December (4.13±0.83 birds per km2), while the highest in August (10.72±1.67 birds per km2). The population density of Black Francolin was low during drought years (4.03±1.02 birds per km2), as compared with high rainfall years (6.38±2.19 birds per km2). Population density of the Grey Francolin was on its lowest during 1996 (5.34±1.12) and the highest in 1999 (7.53±1.14) birds per km2). Their was preponderance of males (male: female ratio: Black = 1.31: 1, Grey 1.21: 1) in both the sexes. There were 0.32±0.09 sub-adult per female (0.14±0.03 sub-adult per adult) in the Black Francolin, while 0.32±0.07 sub-adult per female (0.15±0.03 sub-adult per adult) in the Grey Francolins. The Population of Black (dispersion index 0.60±0.08 and the Grey dispersion index 0.78±0.11) Francolins random tending toward a uniform xviiidispersion was observed in the LSNP. The Black Francolin exhibited a more random in the morning (0.63±0.12) as compared with the evening (0.52±0.20) while the Grey exhibits a more uniform dispersion in morning (0.58±0.10) than in evening (0.98±0.18). A total of 102 species of plants were identified from francolins habitat in LSNP with absolute vegetation cover ranging between 8.35 and 13.75 percent in tropical thorn forest and between 40 and 60 percent in irrigated forest plantations. The Black and the Grey Francolin exhibited a negative yet non – significant correlation co-efficient (0.333, p = 0.35) in their distribution in different stands. The Black Francolin appeared in high densities (11 - 13 birds per km2) in the stands having a high vegetation cover (40 - 46 percent) than (3 – 5 birds per km2) than with low vegetation cover (12 – 14 percent). The Grey Francolin had a lower population (4.66±0.96 birds per km2) in high vegetation cover than that of lower cover (10.08±2.12 birds per km2). No population was observed below 8 percent cover. Correlation and regression was calculated by applying the computer software MINITAB 15 and CANOCO 4.5. The average home range was smaller in the Black (0.51±0.14 km2), as compared with the Grey Francolin (0.61±0.16 km2). Sixty seven percent females of Black Francolins and seventy eight percent of the Grey Francolins laid their clutches between mid March to early May. Average clutch size of 6.56±1.40, the incubation period of 18.53±1.14 days and breeding success of 36±3.18 percent was recorded for Black and clutch size of 7.22±1.23, incubation period, xix17.86±2.10 days and breeding success of 37±3.25 percent were recorded for Grey Francolin. The studies suggest that both the species are adapted to the environmental conditions and vigorously growing population, able to sustain all environmental odds.