| Title |
Monthly abundance patterns and the potential role of waterbirds as phosphorus sources to a hypertrophic Baltic Lagoon |
| Authors |
Morkūnė, Rasa ; Petkuvienė, Jolita ; Bružas, Modestas ; Morkūnas, Julius ; Bartoli, Marco |
| DOI |
10.3390/w12051392 |
| Full Text |
|
| Is Part of |
Water.. Basel : MDPI. 2020, vol. 12, iss. 5, art. no. 1392, p. 1-22.. eISSN 2073-4441 |
| Keywords [eng] |
estuary ; bird ; guilds ; visual counts ; feces ; phosphorus source ; algal blooms |
| Abstract [eng] |
Compared to external loads from tributaries and sediment recycling, the role of waterbirds as phosphorus (P) sources in estuaries is overlooked. We performed monthly ship-based surveys of waterbird abundance in the Lithuanian part of the Curonian Lagoon, calculated their potential P excretion, and compared its relevance to the riverine inputs. Phosphorus excretion rates for the censused species were assessed accounting for variations of body weights, daily feces production and their P content, and assigning species to different feeding and nutrient cycling guilds. During the study period (March–November 2018), 32 waterbird species were censused, varying in abundance from ~18,000–32,000 (October–November) to ~30,000–48,000 individuals (June–September). The estimated avian P loads during the whole study period varied between 3.6 and 25 tons, corresponding to an area load between 8.7 and 60.7 mg P m−2. Waterbird release of reactive P to the system represented a variable but not negligible fraction (1%–12%) of total external P loads, peaking in June–September and coinciding with cyanobacterial blooms. This study is the first in the Baltic Sea region suggesting that waterbirds are potentially important P sources to phytoplankton in large estuaries, in particular, during low discharge periods. |
| Published |
Basel : MDPI |
| Type |
Journal article |
| Language |
English |
| Publication date |
2020 |
| CC license |
|
