Concentration of organochlorine in egg yolk and reproductive success of Egretta garzetta (Linnaeus, 1758) at Wat Tan-en non-hunting area, Phra Nakhorn Si Ayuthaya Province, Thailand

Organochlorine residual concentrations in cattle egret from the Punjab Province, Pakistan

“…Concentration of DDE in eggs collected from heronry from River Chenab (64.1 ng/g) was greater as compared to eggs collected from River Ravi (58.2 ng/g) and Rawal Lake Reservoir (53.1 ng/g). The concentrations measured were less than those reported in grey heron (470 ng/g) from France (De Cruz et al 1997), white-faced ibis (2,100 ng/g) from the USA (King et al 2003), and peregrine falcon (3,900 ng/g) from Zimbabwe (Hartley et al 1995) and were within the range reported in the eggs of little egret from the Wat Tan-en non-hunting area Thailand (Keithmaleesatti et al 2007); however, the residual level recorded in eggs was higher than those in eggs of cattle egret (24 ng/g) from Barberspan and Vaal River (Bouwman et al 2008).…”

“…Birds at higher trophic levels tend to have higher exposure to DDE but not necessarily its effects (Keithmaleesatti et al 2007). The effect of DDE on shell quality is very species specific, e.g., fish-eating bird species are generally most sensitive towards DDE residue burden and eggshell thinning (Burger et al 2007).…”

“…The literature suggested that egg sample size varied considerably among different studies, e.g., egg sample sizes of little egret varied between three and five per heronry (Keithmaleesatti et al 2007), 12 eggs from brown boobies at eight colonies from the northern Gulf of California to southern Mexico (Mellink et al 2009), five to 15 eggs per heronry in the study of Henny et al (2003), three to five eggs per colony of great blue herons (Ardea herodias) from Indiana (Baker and Sepu'lveda 2009), three to 14 eggs of little egrets from three breeding heronries of three selected wetlands of Pakistan (Sanpera et al 2003), five to 11 eggs from two cattle egret heronries from south Africa (Bouwman et al 2008), and 20 eggs of cattle egrets from Tai Lake in China (Dong et al 2004). Therefore, in this study, from each heronry, a total of 10 nests were sampled, and one egg from each nest was collected.…”

“…Their use is becoming widespread, representing a global contamination problem, and had been measured in high concentration even in remote regions such as the Arctic (Mallory et al 2005). These chemicals persist in the environment with long half-lives, are highly volatile, extremely stable, and bio-accumulate (Keithmaleesatti et al 2007). These environmental contaminants are mainly manufactured synthetically, released into the environment as a result of anthropogenic activities, and had been reported worldwide in different physical and biological compartments of terrestrial (Jaspers et al 2007;Cid et al 2007;Qadir et al 2008;Dauwe et al 2009;Qadir and Malik 2009) as well as aquatic ecosystems including pristine Arctic environments (Mallory et al 2005) due to their toxicity, non-biodegradability, and biomagnification at higher trophic levels.…”

Bioaccumulation of organochlorine pesticides in the liver of birds from Boraphet wetland, Thailand

“…OCPs were used extensively in Thailand until 1983; when many compounds were banned by the Thai government (www.thailand.ipm-info.org/ pesticides/pesticides banned.htm). Despite restrictions and bans on the use of many OCPs, their bioaccumulation and detection in the egg yolk of birds at the Wat Tan-En Non-hunting Area, Phranakhon Si Ayutthaya province, central Thailand 9 , and in the aquatic food web at Klong Rangsit, Patum Thani province, central Thailand 10 indicates either continual use or persistence of the compounds in the environment.…”