Henrique Barros stressed the birds “are not unhappy” nor do they need to be “handfed”, and the general population needs to be made more aware of the importance of placing urban waste in the appropriate places.
“If people took care to put waste in the places it should be placed, and if councils made the effort to collect it properly, and if people did not feed the seagulls by hand” it would be halfway towards controlling the invasion of seagulls in urban areas, the public health specialist said.
The phenomenon of the ever-increasing flocks of seagulls is not a case for alarm, he reassured, but “prevention must be constant”.
“There is no need for alarm; this is not like the case of bats that transmitted serious infectious disease in Africa, or like rabies. We are not talking about things like that, but it is possible that if there is a bigger ecological imbalance, some species [such as seagulls] can become carriers of infectious agents”, Mr. Barros emphasised, recalling the debate surrounding “bird flu”.
“What we know nowadays, and this is very clear, is that when we shift ecological balances we create problems,” and in making this change “conditions are created so that we can introduce or circulate an agent that we were not expecting” he explains, noting that seagulls should be eating fish from the sea, not rubbish from cities.
A scientific study has revealed that the seagulls in Porto feed both on muffins and meat in the downtown area, eat fish along the river Douro as far as Pinhão (Vila Real) and scavenge from the Matosinhos market.
According to the Portuguese Society for Bird Studies (SPEA), the increase in seagull attacks in Porto can be explained by the growing number of restaurants near the Douro River, a consequence of the high tourist demand in that area.
Reports of seagulls being nuisances have emerged from north to south of the country in recent years, with the birds now being found in areas which not so long ago would never have been considered their natural habitat, such as inland residential neighbourhoods.
The SPEA has previously confirmed that the seagull population is growing and attributed its inland occupation, particularly in coastal towns and fishing villages, to the “over-abundance of food resources”.
An evident rise in the number of complaints about seagulls’ ‘inland invasion’ and their “constant screeching” keeping readers awake at night was picked up on by The Portugal News as early as 2012.
Nuno Barros of the SPEA confirmed that the seagull population had “been increasing in some points of the country, and subsequently upsetting the locals”.
Identifying the species in question as the yellow-legged-gull (Larus michahellis), which can be found throughout the country, he explained: “In the last few years there has been an expansion of breeding sites, with birds nesting in rooftops of coastal cities like Porto, Peniche, and in the Algarve in cities like Lagos or Portimão”.
Their expansion is mainly related to “the over-abundance of food resources” and, he says, we have no one else to blame for it but ourselves.
“Seagulls feed in dumpsters and human waste, as well as discards from the fishing industry. So if we have to find a guilty party, it is once again, us. We reject most of the fish we take from the sea, we do not effectively clean our fishing ports, we dump our trash in open dumpsters, and we drop our sewage in the sea. All this represents nutrients for the seagulls, opportunistic and smart feeders that are thriving on our lack of care”.
He was, however, careful to highlight that not all seagulls should be tarred with the same brush.
“There are other species of seagull, like Audouin’s Gull (Larus audouinii), that exist in very small numbers, and in Portugal only breed in Castro Marim and Ria Formosa. These birds are in need of concrete conservation actions, for their breeding grounds are overloaded with human disturbance in the breeding season. So let’s be careful, not all seagulls are alike”, he stressed.
The expansion of seagulls into urban areas has been a particularly large problem in Porto, where several studies and reports have been carried out into the phenomenon.
A study named ‘Seagulls in the City’, carried out by municipal company Amporto in collaboration with the Oporto University Interdisciplinary Centre of Marine and Environmental Research (CIIMAR.UP) listed the main issues caused in Oporto by the growing number of gulls.
Key issues are damage caused to property by the acidity of seagull excrement; blocked pipes and drains because of feathers and nest contents, noise pollution, the transmission of pathogens, the disruption of work as well as the enjoyment of urban leisure areas, and bird strikes on aircraft.
Measures suggested in the report to reduce the impact of the gull’s urban expansion include the placing of nets, cables and spikes to prevent the birds from settling; the emission of alarm and predator sounds to deter the birds, and the altering of human habits to significantly eliminate or reduce the availability of food to seagulls.
“The restriction of food resources is the simplest, cheapest and most efficient way of controlling gulls, however, it has the setback of its effects only being seen in the long-run”, the report said.